/**
 * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 * SPDX-License-Identifier: Apache-2.0.
 */

#pragma once
#include <aws/dynamodb/DynamoDB_EXPORTS.h>
#include <aws/dynamodb/model/AttributeValue.h>
#include <aws/dynamodb/model/ComparisonOperator.h>
#include <aws/core/utils/memory/stl/AWSVector.h>
#include <utility>

namespace Aws
{
namespace Utils
{
namespace Json
{
  class JsonValue;
  class JsonView;
} // namespace Json
} // namespace Utils
namespace DynamoDB
{
namespace Model
{

  /**
   * <p>Represents a condition to be compared with an attribute value. This condition
   * can be used with <code>DeleteItem</code>, <code>PutItem</code>, or
   * <code>UpdateItem</code> operations; if the comparison evaluates to true, the
   * operation succeeds; if not, the operation fails. You can use
   * <code>ExpectedAttributeValue</code> in one of two different ways:</p> <ul> <li>
   * <p>Use <code>AttributeValueList</code> to specify one or more values to compare
   * against an attribute. Use <code>ComparisonOperator</code> to specify how you
   * want to perform the comparison. If the comparison evaluates to true, then the
   * conditional operation succeeds.</p> </li> <li> <p>Use <code>Value</code> to
   * specify a value that DynamoDB will compare against an attribute. If the values
   * match, then <code>ExpectedAttributeValue</code> evaluates to true and the
   * conditional operation succeeds. Optionally, you can also set <code>Exists</code>
   * to false, indicating that you <i>do not</i> expect to find the attribute value
   * in the table. In this case, the conditional operation succeeds only if the
   * comparison evaluates to false.</p> </li> </ul> <p> <code>Value</code> and
   * <code>Exists</code> are incompatible with <code>AttributeValueList</code> and
   * <code>ComparisonOperator</code>. Note that if you use both sets of parameters at
   * once, DynamoDB will return a <code>ValidationException</code>
   * exception.</p><p><h3>See Also:</h3>   <a
   * href="http://docs.aws.amazon.com/goto/WebAPI/dynamodb-2012-08-10/ExpectedAttributeValue">AWS
   * API Reference</a></p>
   */
  class ExpectedAttributeValue
  {
  public:
    AWS_DYNAMODB_API ExpectedAttributeValue();
    AWS_DYNAMODB_API ExpectedAttributeValue(Aws::Utils::Json::JsonView jsonValue);
    AWS_DYNAMODB_API ExpectedAttributeValue& operator=(Aws::Utils::Json::JsonView jsonValue);
    AWS_DYNAMODB_API Aws::Utils::Json::JsonValue Jsonize() const;


    /**
     * <p>Represents the data for the expected attribute.</p> <p>Each attribute value
     * is described as a name-value pair. The name is the data type, and the value is
     * the data itself.</p> <p>For more information, see <a
     * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/HowItWorks.NamingRulesDataTypes.html#HowItWorks.DataTypes">Data
     * Types</a> in the <i>Amazon DynamoDB Developer Guide</i>.</p>
     */
    inline const AttributeValue& GetValue() const{ return m_value; }

    /**
     * <p>Represents the data for the expected attribute.</p> <p>Each attribute value
     * is described as a name-value pair. The name is the data type, and the value is
     * the data itself.</p> <p>For more information, see <a
     * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/HowItWorks.NamingRulesDataTypes.html#HowItWorks.DataTypes">Data
     * Types</a> in the <i>Amazon DynamoDB Developer Guide</i>.</p>
     */
    inline bool ValueHasBeenSet() const { return m_valueHasBeenSet; }

    /**
     * <p>Represents the data for the expected attribute.</p> <p>Each attribute value
     * is described as a name-value pair. The name is the data type, and the value is
     * the data itself.</p> <p>For more information, see <a
     * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/HowItWorks.NamingRulesDataTypes.html#HowItWorks.DataTypes">Data
     * Types</a> in the <i>Amazon DynamoDB Developer Guide</i>.</p>
     */
    inline void SetValue(const AttributeValue& value) { m_valueHasBeenSet = true; m_value = value; }

    /**
     * <p>Represents the data for the expected attribute.</p> <p>Each attribute value
     * is described as a name-value pair. The name is the data type, and the value is
     * the data itself.</p> <p>For more information, see <a
     * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/HowItWorks.NamingRulesDataTypes.html#HowItWorks.DataTypes">Data
     * Types</a> in the <i>Amazon DynamoDB Developer Guide</i>.</p>
     */
    inline void SetValue(AttributeValue&& value) { m_valueHasBeenSet = true; m_value = std::move(value); }

    /**
     * <p>Represents the data for the expected attribute.</p> <p>Each attribute value
     * is described as a name-value pair. The name is the data type, and the value is
     * the data itself.</p> <p>For more information, see <a
     * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/HowItWorks.NamingRulesDataTypes.html#HowItWorks.DataTypes">Data
     * Types</a> in the <i>Amazon DynamoDB Developer Guide</i>.</p>
     */
    inline ExpectedAttributeValue& WithValue(const AttributeValue& value) { SetValue(value); return *this;}

    /**
     * <p>Represents the data for the expected attribute.</p> <p>Each attribute value
     * is described as a name-value pair. The name is the data type, and the value is
     * the data itself.</p> <p>For more information, see <a
     * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/HowItWorks.NamingRulesDataTypes.html#HowItWorks.DataTypes">Data
     * Types</a> in the <i>Amazon DynamoDB Developer Guide</i>.</p>
     */
    inline ExpectedAttributeValue& WithValue(AttributeValue&& value) { SetValue(std::move(value)); return *this;}


    /**
     * <p>Causes DynamoDB to evaluate the value before attempting a conditional
     * operation:</p> <ul> <li> <p>If <code>Exists</code> is <code>true</code>,
     * DynamoDB will check to see if that attribute value already exists in the table.
     * If it is found, then the operation succeeds. If it is not found, the operation
     * fails with a <code>ConditionCheckFailedException</code>.</p> </li> <li> <p>If
     * <code>Exists</code> is <code>false</code>, DynamoDB assumes that the attribute
     * value does not exist in the table. If in fact the value does not exist, then the
     * assumption is valid and the operation succeeds. If the value is found, despite
     * the assumption that it does not exist, the operation fails with a
     * <code>ConditionCheckFailedException</code>.</p> </li> </ul> <p>The default
     * setting for <code>Exists</code> is <code>true</code>. If you supply a
     * <code>Value</code> all by itself, DynamoDB assumes the attribute exists: You
     * don't have to set <code>Exists</code> to <code>true</code>, because it is
     * implied.</p> <p>DynamoDB returns a <code>ValidationException</code> if:</p> <ul>
     * <li> <p> <code>Exists</code> is <code>true</code> but there is no
     * <code>Value</code> to check. (You expect a value to exist, but don't specify
     * what that value is.)</p> </li> <li> <p> <code>Exists</code> is
     * <code>false</code> but you also provide a <code>Value</code>. (You cannot expect
     * an attribute to have a value, while also expecting it not to exist.)</p> </li>
     * </ul>
     */
    inline bool GetExists() const{ return m_exists; }

    /**
     * <p>Causes DynamoDB to evaluate the value before attempting a conditional
     * operation:</p> <ul> <li> <p>If <code>Exists</code> is <code>true</code>,
     * DynamoDB will check to see if that attribute value already exists in the table.
     * If it is found, then the operation succeeds. If it is not found, the operation
     * fails with a <code>ConditionCheckFailedException</code>.</p> </li> <li> <p>If
     * <code>Exists</code> is <code>false</code>, DynamoDB assumes that the attribute
     * value does not exist in the table. If in fact the value does not exist, then the
     * assumption is valid and the operation succeeds. If the value is found, despite
     * the assumption that it does not exist, the operation fails with a
     * <code>ConditionCheckFailedException</code>.</p> </li> </ul> <p>The default
     * setting for <code>Exists</code> is <code>true</code>. If you supply a
     * <code>Value</code> all by itself, DynamoDB assumes the attribute exists: You
     * don't have to set <code>Exists</code> to <code>true</code>, because it is
     * implied.</p> <p>DynamoDB returns a <code>ValidationException</code> if:</p> <ul>
     * <li> <p> <code>Exists</code> is <code>true</code> but there is no
     * <code>Value</code> to check. (You expect a value to exist, but don't specify
     * what that value is.)</p> </li> <li> <p> <code>Exists</code> is
     * <code>false</code> but you also provide a <code>Value</code>. (You cannot expect
     * an attribute to have a value, while also expecting it not to exist.)</p> </li>
     * </ul>
     */
    inline bool ExistsHasBeenSet() const { return m_existsHasBeenSet; }

    /**
     * <p>Causes DynamoDB to evaluate the value before attempting a conditional
     * operation:</p> <ul> <li> <p>If <code>Exists</code> is <code>true</code>,
     * DynamoDB will check to see if that attribute value already exists in the table.
     * If it is found, then the operation succeeds. If it is not found, the operation
     * fails with a <code>ConditionCheckFailedException</code>.</p> </li> <li> <p>If
     * <code>Exists</code> is <code>false</code>, DynamoDB assumes that the attribute
     * value does not exist in the table. If in fact the value does not exist, then the
     * assumption is valid and the operation succeeds. If the value is found, despite
     * the assumption that it does not exist, the operation fails with a
     * <code>ConditionCheckFailedException</code>.</p> </li> </ul> <p>The default
     * setting for <code>Exists</code> is <code>true</code>. If you supply a
     * <code>Value</code> all by itself, DynamoDB assumes the attribute exists: You
     * don't have to set <code>Exists</code> to <code>true</code>, because it is
     * implied.</p> <p>DynamoDB returns a <code>ValidationException</code> if:</p> <ul>
     * <li> <p> <code>Exists</code> is <code>true</code> but there is no
     * <code>Value</code> to check. (You expect a value to exist, but don't specify
     * what that value is.)</p> </li> <li> <p> <code>Exists</code> is
     * <code>false</code> but you also provide a <code>Value</code>. (You cannot expect
     * an attribute to have a value, while also expecting it not to exist.)</p> </li>
     * </ul>
     */
    inline void SetExists(bool value) { m_existsHasBeenSet = true; m_exists = value; }

    /**
     * <p>Causes DynamoDB to evaluate the value before attempting a conditional
     * operation:</p> <ul> <li> <p>If <code>Exists</code> is <code>true</code>,
     * DynamoDB will check to see if that attribute value already exists in the table.
     * If it is found, then the operation succeeds. If it is not found, the operation
     * fails with a <code>ConditionCheckFailedException</code>.</p> </li> <li> <p>If
     * <code>Exists</code> is <code>false</code>, DynamoDB assumes that the attribute
     * value does not exist in the table. If in fact the value does not exist, then the
     * assumption is valid and the operation succeeds. If the value is found, despite
     * the assumption that it does not exist, the operation fails with a
     * <code>ConditionCheckFailedException</code>.</p> </li> </ul> <p>The default
     * setting for <code>Exists</code> is <code>true</code>. If you supply a
     * <code>Value</code> all by itself, DynamoDB assumes the attribute exists: You
     * don't have to set <code>Exists</code> to <code>true</code>, because it is
     * implied.</p> <p>DynamoDB returns a <code>ValidationException</code> if:</p> <ul>
     * <li> <p> <code>Exists</code> is <code>true</code> but there is no
     * <code>Value</code> to check. (You expect a value to exist, but don't specify
     * what that value is.)</p> </li> <li> <p> <code>Exists</code> is
     * <code>false</code> but you also provide a <code>Value</code>. (You cannot expect
     * an attribute to have a value, while also expecting it not to exist.)</p> </li>
     * </ul>
     */
    inline ExpectedAttributeValue& WithExists(bool value) { SetExists(value); return *this;}


    /**
     * <p>A comparator for evaluating attributes in the
     * <code>AttributeValueList</code>. For example, equals, greater than, less than,
     * etc.</p> <p>The following comparison operators are available:</p> <p> <code>EQ |
     * NE | LE | LT | GE | GT | NOT_NULL | NULL | CONTAINS | NOT_CONTAINS | BEGINS_WITH
     * | IN | BETWEEN</code> </p> <p>The following are descriptions of each comparison
     * operator.</p> <ul> <li> <p> <code>EQ</code> : Equal. <code>EQ</code> is
     * supported for all data types, including lists and maps.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, Binary, String Set, Number Set, or Binary Set.
     * If an item contains an <code>AttributeValue</code> element of a different type
     * than the one provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not equal <code>{"NS":["6", "2", "1"]}</code>.</p>
     * <p/> </li> <li> <p> <code>NE</code> : Not equal. <code>NE</code> is supported
     * for all data types, including lists and maps.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * of type String, Number, Binary, String Set, Number Set, or Binary Set. If an
     * item contains an <code>AttributeValue</code> of a different type than the one
     * provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not equal <code>{"NS":["6", "2", "1"]}</code>.</p>
     * <p/> </li> <li> <p> <code>LE</code> : Less than or equal. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If an item contains
     * an <code>AttributeValue</code> element of a different type than the one provided
     * in the request, the value does not match. For example, <code>{"S":"6"}</code>
     * does not equal <code>{"N":"6"}</code>. Also, <code>{"N":"6"}</code> does not
     * compare to <code>{"NS":["6", "2", "1"]}</code>.</p> <p/> </li> <li> <p>
     * <code>LT</code> : Less than. </p> <p> <code>AttributeValueList</code> can
     * contain only one <code>AttributeValue</code> of type String, Number, or Binary
     * (not a set type). If an item contains an <code>AttributeValue</code> element of
     * a different type than the one provided in the request, the value does not match.
     * For example, <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2",
     * "1"]}</code>.</p> <p/> </li> <li> <p> <code>GE</code> : Greater than or equal.
     * </p> <p> <code>AttributeValueList</code> can contain only one
     * <code>AttributeValue</code> element of type String, Number, or Binary (not a set
     * type). If an item contains an <code>AttributeValue</code> element of a different
     * type than the one provided in the request, the value does not match. For
     * example, <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2",
     * "1"]}</code>.</p> <p/> </li> <li> <p> <code>GT</code> : Greater than. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If an item contains
     * an <code>AttributeValue</code> element of a different type than the one provided
     * in the request, the value does not match. For example, <code>{"S":"6"}</code>
     * does not equal <code>{"N":"6"}</code>. Also, <code>{"N":"6"}</code> does not
     * compare to <code>{"NS":["6", "2", "1"]}</code>.</p> <p/> </li> <li> <p>
     * <code>NOT_NULL</code> : The attribute exists. <code>NOT_NULL</code> is supported
     * for all data types, including lists and maps.</p>  <p>This operator tests
     * for the existence of an attribute, not its data type. If the data type of
     * attribute "<code>a</code>" is null, and you evaluate it using
     * <code>NOT_NULL</code>, the result is a Boolean <code>true</code>. This result is
     * because the attribute "<code>a</code>" exists; its data type is not relevant to
     * the <code>NOT_NULL</code> comparison operator.</p>  </li> <li> <p>
     * <code>NULL</code> : The attribute does not exist. <code>NULL</code> is supported
     * for all data types, including lists and maps.</p>  <p>This operator tests
     * for the nonexistence of an attribute, not its data type. If the data type of
     * attribute "<code>a</code>" is null, and you evaluate it using <code>NULL</code>,
     * the result is a Boolean <code>false</code>. This is because the attribute
     * "<code>a</code>" exists; its data type is not relevant to the <code>NULL</code>
     * comparison operator.</p>  </li> <li> <p> <code>CONTAINS</code> : Checks
     * for a subsequence, or value in a set.</p> <p> <code>AttributeValueList</code>
     * can contain only one <code>AttributeValue</code> element of type String, Number,
     * or Binary (not a set type). If the target attribute of the comparison is of type
     * String, then the operator checks for a substring match. If the target attribute
     * of the comparison is of type Binary, then the operator looks for a subsequence
     * of the target that matches the input. If the target attribute of the comparison
     * is a set ("<code>SS</code>", "<code>NS</code>", or "<code>BS</code>"), then the
     * operator evaluates to true if it finds an exact match with any member of the
     * set.</p> <p>CONTAINS is supported for lists: When evaluating "<code>a CONTAINS
     * b</code>", "<code>a</code>" can be a list; however, "<code>b</code>" cannot be a
     * set, a map, or a list.</p> </li> <li> <p> <code>NOT_CONTAINS</code> : Checks for
     * absence of a subsequence, or absence of a value in a set.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If the target
     * attribute of the comparison is a String, then the operator checks for the
     * absence of a substring match. If the target attribute of the comparison is
     * Binary, then the operator checks for the absence of a subsequence of the target
     * that matches the input. If the target attribute of the comparison is a set
     * ("<code>SS</code>", "<code>NS</code>", or "<code>BS</code>"), then the operator
     * evaluates to true if it <i>does not</i> find an exact match with any member of
     * the set.</p> <p>NOT_CONTAINS is supported for lists: When evaluating "<code>a
     * NOT CONTAINS b</code>", "<code>a</code>" can be a list; however,
     * "<code>b</code>" cannot be a set, a map, or a list.</p> </li> <li> <p>
     * <code>BEGINS_WITH</code> : Checks for a prefix. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * of type String or Binary (not a Number or a set type). The target attribute of
     * the comparison must be of type String or Binary (not a Number or a set
     * type).</p> <p/> </li> <li> <p> <code>IN</code> : Checks for matching elements in
     * a list.</p> <p> <code>AttributeValueList</code> can contain one or more
     * <code>AttributeValue</code> elements of type String, Number, or Binary. These
     * attributes are compared against an existing attribute of an item. If any
     * elements of the input are equal to the item attribute, the expression evaluates
     * to true.</p> </li> <li> <p> <code>BETWEEN</code> : Greater than or equal to the
     * first value, and less than or equal to the second value. </p> <p>
     * <code>AttributeValueList</code> must contain two <code>AttributeValue</code>
     * elements of the same type, either String, Number, or Binary (not a set type). A
     * target attribute matches if the target value is greater than, or equal to, the
     * first element and less than, or equal to, the second element. If an item
     * contains an <code>AttributeValue</code> element of a different type than the one
     * provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not compare to <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2", "1"]}</code>
     * </p> </li> </ul>
     */
    inline const ComparisonOperator& GetComparisonOperator() const{ return m_comparisonOperator; }

    /**
     * <p>A comparator for evaluating attributes in the
     * <code>AttributeValueList</code>. For example, equals, greater than, less than,
     * etc.</p> <p>The following comparison operators are available:</p> <p> <code>EQ |
     * NE | LE | LT | GE | GT | NOT_NULL | NULL | CONTAINS | NOT_CONTAINS | BEGINS_WITH
     * | IN | BETWEEN</code> </p> <p>The following are descriptions of each comparison
     * operator.</p> <ul> <li> <p> <code>EQ</code> : Equal. <code>EQ</code> is
     * supported for all data types, including lists and maps.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, Binary, String Set, Number Set, or Binary Set.
     * If an item contains an <code>AttributeValue</code> element of a different type
     * than the one provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not equal <code>{"NS":["6", "2", "1"]}</code>.</p>
     * <p/> </li> <li> <p> <code>NE</code> : Not equal. <code>NE</code> is supported
     * for all data types, including lists and maps.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * of type String, Number, Binary, String Set, Number Set, or Binary Set. If an
     * item contains an <code>AttributeValue</code> of a different type than the one
     * provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not equal <code>{"NS":["6", "2", "1"]}</code>.</p>
     * <p/> </li> <li> <p> <code>LE</code> : Less than or equal. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If an item contains
     * an <code>AttributeValue</code> element of a different type than the one provided
     * in the request, the value does not match. For example, <code>{"S":"6"}</code>
     * does not equal <code>{"N":"6"}</code>. Also, <code>{"N":"6"}</code> does not
     * compare to <code>{"NS":["6", "2", "1"]}</code>.</p> <p/> </li> <li> <p>
     * <code>LT</code> : Less than. </p> <p> <code>AttributeValueList</code> can
     * contain only one <code>AttributeValue</code> of type String, Number, or Binary
     * (not a set type). If an item contains an <code>AttributeValue</code> element of
     * a different type than the one provided in the request, the value does not match.
     * For example, <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2",
     * "1"]}</code>.</p> <p/> </li> <li> <p> <code>GE</code> : Greater than or equal.
     * </p> <p> <code>AttributeValueList</code> can contain only one
     * <code>AttributeValue</code> element of type String, Number, or Binary (not a set
     * type). If an item contains an <code>AttributeValue</code> element of a different
     * type than the one provided in the request, the value does not match. For
     * example, <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2",
     * "1"]}</code>.</p> <p/> </li> <li> <p> <code>GT</code> : Greater than. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If an item contains
     * an <code>AttributeValue</code> element of a different type than the one provided
     * in the request, the value does not match. For example, <code>{"S":"6"}</code>
     * does not equal <code>{"N":"6"}</code>. Also, <code>{"N":"6"}</code> does not
     * compare to <code>{"NS":["6", "2", "1"]}</code>.</p> <p/> </li> <li> <p>
     * <code>NOT_NULL</code> : The attribute exists. <code>NOT_NULL</code> is supported
     * for all data types, including lists and maps.</p>  <p>This operator tests
     * for the existence of an attribute, not its data type. If the data type of
     * attribute "<code>a</code>" is null, and you evaluate it using
     * <code>NOT_NULL</code>, the result is a Boolean <code>true</code>. This result is
     * because the attribute "<code>a</code>" exists; its data type is not relevant to
     * the <code>NOT_NULL</code> comparison operator.</p>  </li> <li> <p>
     * <code>NULL</code> : The attribute does not exist. <code>NULL</code> is supported
     * for all data types, including lists and maps.</p>  <p>This operator tests
     * for the nonexistence of an attribute, not its data type. If the data type of
     * attribute "<code>a</code>" is null, and you evaluate it using <code>NULL</code>,
     * the result is a Boolean <code>false</code>. This is because the attribute
     * "<code>a</code>" exists; its data type is not relevant to the <code>NULL</code>
     * comparison operator.</p>  </li> <li> <p> <code>CONTAINS</code> : Checks
     * for a subsequence, or value in a set.</p> <p> <code>AttributeValueList</code>
     * can contain only one <code>AttributeValue</code> element of type String, Number,
     * or Binary (not a set type). If the target attribute of the comparison is of type
     * String, then the operator checks for a substring match. If the target attribute
     * of the comparison is of type Binary, then the operator looks for a subsequence
     * of the target that matches the input. If the target attribute of the comparison
     * is a set ("<code>SS</code>", "<code>NS</code>", or "<code>BS</code>"), then the
     * operator evaluates to true if it finds an exact match with any member of the
     * set.</p> <p>CONTAINS is supported for lists: When evaluating "<code>a CONTAINS
     * b</code>", "<code>a</code>" can be a list; however, "<code>b</code>" cannot be a
     * set, a map, or a list.</p> </li> <li> <p> <code>NOT_CONTAINS</code> : Checks for
     * absence of a subsequence, or absence of a value in a set.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If the target
     * attribute of the comparison is a String, then the operator checks for the
     * absence of a substring match. If the target attribute of the comparison is
     * Binary, then the operator checks for the absence of a subsequence of the target
     * that matches the input. If the target attribute of the comparison is a set
     * ("<code>SS</code>", "<code>NS</code>", or "<code>BS</code>"), then the operator
     * evaluates to true if it <i>does not</i> find an exact match with any member of
     * the set.</p> <p>NOT_CONTAINS is supported for lists: When evaluating "<code>a
     * NOT CONTAINS b</code>", "<code>a</code>" can be a list; however,
     * "<code>b</code>" cannot be a set, a map, or a list.</p> </li> <li> <p>
     * <code>BEGINS_WITH</code> : Checks for a prefix. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * of type String or Binary (not a Number or a set type). The target attribute of
     * the comparison must be of type String or Binary (not a Number or a set
     * type).</p> <p/> </li> <li> <p> <code>IN</code> : Checks for matching elements in
     * a list.</p> <p> <code>AttributeValueList</code> can contain one or more
     * <code>AttributeValue</code> elements of type String, Number, or Binary. These
     * attributes are compared against an existing attribute of an item. If any
     * elements of the input are equal to the item attribute, the expression evaluates
     * to true.</p> </li> <li> <p> <code>BETWEEN</code> : Greater than or equal to the
     * first value, and less than or equal to the second value. </p> <p>
     * <code>AttributeValueList</code> must contain two <code>AttributeValue</code>
     * elements of the same type, either String, Number, or Binary (not a set type). A
     * target attribute matches if the target value is greater than, or equal to, the
     * first element and less than, or equal to, the second element. If an item
     * contains an <code>AttributeValue</code> element of a different type than the one
     * provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not compare to <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2", "1"]}</code>
     * </p> </li> </ul>
     */
    inline bool ComparisonOperatorHasBeenSet() const { return m_comparisonOperatorHasBeenSet; }

    /**
     * <p>A comparator for evaluating attributes in the
     * <code>AttributeValueList</code>. For example, equals, greater than, less than,
     * etc.</p> <p>The following comparison operators are available:</p> <p> <code>EQ |
     * NE | LE | LT | GE | GT | NOT_NULL | NULL | CONTAINS | NOT_CONTAINS | BEGINS_WITH
     * | IN | BETWEEN</code> </p> <p>The following are descriptions of each comparison
     * operator.</p> <ul> <li> <p> <code>EQ</code> : Equal. <code>EQ</code> is
     * supported for all data types, including lists and maps.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, Binary, String Set, Number Set, or Binary Set.
     * If an item contains an <code>AttributeValue</code> element of a different type
     * than the one provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not equal <code>{"NS":["6", "2", "1"]}</code>.</p>
     * <p/> </li> <li> <p> <code>NE</code> : Not equal. <code>NE</code> is supported
     * for all data types, including lists and maps.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * of type String, Number, Binary, String Set, Number Set, or Binary Set. If an
     * item contains an <code>AttributeValue</code> of a different type than the one
     * provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not equal <code>{"NS":["6", "2", "1"]}</code>.</p>
     * <p/> </li> <li> <p> <code>LE</code> : Less than or equal. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If an item contains
     * an <code>AttributeValue</code> element of a different type than the one provided
     * in the request, the value does not match. For example, <code>{"S":"6"}</code>
     * does not equal <code>{"N":"6"}</code>. Also, <code>{"N":"6"}</code> does not
     * compare to <code>{"NS":["6", "2", "1"]}</code>.</p> <p/> </li> <li> <p>
     * <code>LT</code> : Less than. </p> <p> <code>AttributeValueList</code> can
     * contain only one <code>AttributeValue</code> of type String, Number, or Binary
     * (not a set type). If an item contains an <code>AttributeValue</code> element of
     * a different type than the one provided in the request, the value does not match.
     * For example, <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2",
     * "1"]}</code>.</p> <p/> </li> <li> <p> <code>GE</code> : Greater than or equal.
     * </p> <p> <code>AttributeValueList</code> can contain only one
     * <code>AttributeValue</code> element of type String, Number, or Binary (not a set
     * type). If an item contains an <code>AttributeValue</code> element of a different
     * type than the one provided in the request, the value does not match. For
     * example, <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2",
     * "1"]}</code>.</p> <p/> </li> <li> <p> <code>GT</code> : Greater than. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If an item contains
     * an <code>AttributeValue</code> element of a different type than the one provided
     * in the request, the value does not match. For example, <code>{"S":"6"}</code>
     * does not equal <code>{"N":"6"}</code>. Also, <code>{"N":"6"}</code> does not
     * compare to <code>{"NS":["6", "2", "1"]}</code>.</p> <p/> </li> <li> <p>
     * <code>NOT_NULL</code> : The attribute exists. <code>NOT_NULL</code> is supported
     * for all data types, including lists and maps.</p>  <p>This operator tests
     * for the existence of an attribute, not its data type. If the data type of
     * attribute "<code>a</code>" is null, and you evaluate it using
     * <code>NOT_NULL</code>, the result is a Boolean <code>true</code>. This result is
     * because the attribute "<code>a</code>" exists; its data type is not relevant to
     * the <code>NOT_NULL</code> comparison operator.</p>  </li> <li> <p>
     * <code>NULL</code> : The attribute does not exist. <code>NULL</code> is supported
     * for all data types, including lists and maps.</p>  <p>This operator tests
     * for the nonexistence of an attribute, not its data type. If the data type of
     * attribute "<code>a</code>" is null, and you evaluate it using <code>NULL</code>,
     * the result is a Boolean <code>false</code>. This is because the attribute
     * "<code>a</code>" exists; its data type is not relevant to the <code>NULL</code>
     * comparison operator.</p>  </li> <li> <p> <code>CONTAINS</code> : Checks
     * for a subsequence, or value in a set.</p> <p> <code>AttributeValueList</code>
     * can contain only one <code>AttributeValue</code> element of type String, Number,
     * or Binary (not a set type). If the target attribute of the comparison is of type
     * String, then the operator checks for a substring match. If the target attribute
     * of the comparison is of type Binary, then the operator looks for a subsequence
     * of the target that matches the input. If the target attribute of the comparison
     * is a set ("<code>SS</code>", "<code>NS</code>", or "<code>BS</code>"), then the
     * operator evaluates to true if it finds an exact match with any member of the
     * set.</p> <p>CONTAINS is supported for lists: When evaluating "<code>a CONTAINS
     * b</code>", "<code>a</code>" can be a list; however, "<code>b</code>" cannot be a
     * set, a map, or a list.</p> </li> <li> <p> <code>NOT_CONTAINS</code> : Checks for
     * absence of a subsequence, or absence of a value in a set.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If the target
     * attribute of the comparison is a String, then the operator checks for the
     * absence of a substring match. If the target attribute of the comparison is
     * Binary, then the operator checks for the absence of a subsequence of the target
     * that matches the input. If the target attribute of the comparison is a set
     * ("<code>SS</code>", "<code>NS</code>", or "<code>BS</code>"), then the operator
     * evaluates to true if it <i>does not</i> find an exact match with any member of
     * the set.</p> <p>NOT_CONTAINS is supported for lists: When evaluating "<code>a
     * NOT CONTAINS b</code>", "<code>a</code>" can be a list; however,
     * "<code>b</code>" cannot be a set, a map, or a list.</p> </li> <li> <p>
     * <code>BEGINS_WITH</code> : Checks for a prefix. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * of type String or Binary (not a Number or a set type). The target attribute of
     * the comparison must be of type String or Binary (not a Number or a set
     * type).</p> <p/> </li> <li> <p> <code>IN</code> : Checks for matching elements in
     * a list.</p> <p> <code>AttributeValueList</code> can contain one or more
     * <code>AttributeValue</code> elements of type String, Number, or Binary. These
     * attributes are compared against an existing attribute of an item. If any
     * elements of the input are equal to the item attribute, the expression evaluates
     * to true.</p> </li> <li> <p> <code>BETWEEN</code> : Greater than or equal to the
     * first value, and less than or equal to the second value. </p> <p>
     * <code>AttributeValueList</code> must contain two <code>AttributeValue</code>
     * elements of the same type, either String, Number, or Binary (not a set type). A
     * target attribute matches if the target value is greater than, or equal to, the
     * first element and less than, or equal to, the second element. If an item
     * contains an <code>AttributeValue</code> element of a different type than the one
     * provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not compare to <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2", "1"]}</code>
     * </p> </li> </ul>
     */
    inline void SetComparisonOperator(const ComparisonOperator& value) { m_comparisonOperatorHasBeenSet = true; m_comparisonOperator = value; }

    /**
     * <p>A comparator for evaluating attributes in the
     * <code>AttributeValueList</code>. For example, equals, greater than, less than,
     * etc.</p> <p>The following comparison operators are available:</p> <p> <code>EQ |
     * NE | LE | LT | GE | GT | NOT_NULL | NULL | CONTAINS | NOT_CONTAINS | BEGINS_WITH
     * | IN | BETWEEN</code> </p> <p>The following are descriptions of each comparison
     * operator.</p> <ul> <li> <p> <code>EQ</code> : Equal. <code>EQ</code> is
     * supported for all data types, including lists and maps.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, Binary, String Set, Number Set, or Binary Set.
     * If an item contains an <code>AttributeValue</code> element of a different type
     * than the one provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not equal <code>{"NS":["6", "2", "1"]}</code>.</p>
     * <p/> </li> <li> <p> <code>NE</code> : Not equal. <code>NE</code> is supported
     * for all data types, including lists and maps.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * of type String, Number, Binary, String Set, Number Set, or Binary Set. If an
     * item contains an <code>AttributeValue</code> of a different type than the one
     * provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not equal <code>{"NS":["6", "2", "1"]}</code>.</p>
     * <p/> </li> <li> <p> <code>LE</code> : Less than or equal. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If an item contains
     * an <code>AttributeValue</code> element of a different type than the one provided
     * in the request, the value does not match. For example, <code>{"S":"6"}</code>
     * does not equal <code>{"N":"6"}</code>. Also, <code>{"N":"6"}</code> does not
     * compare to <code>{"NS":["6", "2", "1"]}</code>.</p> <p/> </li> <li> <p>
     * <code>LT</code> : Less than. </p> <p> <code>AttributeValueList</code> can
     * contain only one <code>AttributeValue</code> of type String, Number, or Binary
     * (not a set type). If an item contains an <code>AttributeValue</code> element of
     * a different type than the one provided in the request, the value does not match.
     * For example, <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2",
     * "1"]}</code>.</p> <p/> </li> <li> <p> <code>GE</code> : Greater than or equal.
     * </p> <p> <code>AttributeValueList</code> can contain only one
     * <code>AttributeValue</code> element of type String, Number, or Binary (not a set
     * type). If an item contains an <code>AttributeValue</code> element of a different
     * type than the one provided in the request, the value does not match. For
     * example, <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2",
     * "1"]}</code>.</p> <p/> </li> <li> <p> <code>GT</code> : Greater than. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If an item contains
     * an <code>AttributeValue</code> element of a different type than the one provided
     * in the request, the value does not match. For example, <code>{"S":"6"}</code>
     * does not equal <code>{"N":"6"}</code>. Also, <code>{"N":"6"}</code> does not
     * compare to <code>{"NS":["6", "2", "1"]}</code>.</p> <p/> </li> <li> <p>
     * <code>NOT_NULL</code> : The attribute exists. <code>NOT_NULL</code> is supported
     * for all data types, including lists and maps.</p>  <p>This operator tests
     * for the existence of an attribute, not its data type. If the data type of
     * attribute "<code>a</code>" is null, and you evaluate it using
     * <code>NOT_NULL</code>, the result is a Boolean <code>true</code>. This result is
     * because the attribute "<code>a</code>" exists; its data type is not relevant to
     * the <code>NOT_NULL</code> comparison operator.</p>  </li> <li> <p>
     * <code>NULL</code> : The attribute does not exist. <code>NULL</code> is supported
     * for all data types, including lists and maps.</p>  <p>This operator tests
     * for the nonexistence of an attribute, not its data type. If the data type of
     * attribute "<code>a</code>" is null, and you evaluate it using <code>NULL</code>,
     * the result is a Boolean <code>false</code>. This is because the attribute
     * "<code>a</code>" exists; its data type is not relevant to the <code>NULL</code>
     * comparison operator.</p>  </li> <li> <p> <code>CONTAINS</code> : Checks
     * for a subsequence, or value in a set.</p> <p> <code>AttributeValueList</code>
     * can contain only one <code>AttributeValue</code> element of type String, Number,
     * or Binary (not a set type). If the target attribute of the comparison is of type
     * String, then the operator checks for a substring match. If the target attribute
     * of the comparison is of type Binary, then the operator looks for a subsequence
     * of the target that matches the input. If the target attribute of the comparison
     * is a set ("<code>SS</code>", "<code>NS</code>", or "<code>BS</code>"), then the
     * operator evaluates to true if it finds an exact match with any member of the
     * set.</p> <p>CONTAINS is supported for lists: When evaluating "<code>a CONTAINS
     * b</code>", "<code>a</code>" can be a list; however, "<code>b</code>" cannot be a
     * set, a map, or a list.</p> </li> <li> <p> <code>NOT_CONTAINS</code> : Checks for
     * absence of a subsequence, or absence of a value in a set.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If the target
     * attribute of the comparison is a String, then the operator checks for the
     * absence of a substring match. If the target attribute of the comparison is
     * Binary, then the operator checks for the absence of a subsequence of the target
     * that matches the input. If the target attribute of the comparison is a set
     * ("<code>SS</code>", "<code>NS</code>", or "<code>BS</code>"), then the operator
     * evaluates to true if it <i>does not</i> find an exact match with any member of
     * the set.</p> <p>NOT_CONTAINS is supported for lists: When evaluating "<code>a
     * NOT CONTAINS b</code>", "<code>a</code>" can be a list; however,
     * "<code>b</code>" cannot be a set, a map, or a list.</p> </li> <li> <p>
     * <code>BEGINS_WITH</code> : Checks for a prefix. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * of type String or Binary (not a Number or a set type). The target attribute of
     * the comparison must be of type String or Binary (not a Number or a set
     * type).</p> <p/> </li> <li> <p> <code>IN</code> : Checks for matching elements in
     * a list.</p> <p> <code>AttributeValueList</code> can contain one or more
     * <code>AttributeValue</code> elements of type String, Number, or Binary. These
     * attributes are compared against an existing attribute of an item. If any
     * elements of the input are equal to the item attribute, the expression evaluates
     * to true.</p> </li> <li> <p> <code>BETWEEN</code> : Greater than or equal to the
     * first value, and less than or equal to the second value. </p> <p>
     * <code>AttributeValueList</code> must contain two <code>AttributeValue</code>
     * elements of the same type, either String, Number, or Binary (not a set type). A
     * target attribute matches if the target value is greater than, or equal to, the
     * first element and less than, or equal to, the second element. If an item
     * contains an <code>AttributeValue</code> element of a different type than the one
     * provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not compare to <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2", "1"]}</code>
     * </p> </li> </ul>
     */
    inline void SetComparisonOperator(ComparisonOperator&& value) { m_comparisonOperatorHasBeenSet = true; m_comparisonOperator = std::move(value); }

    /**
     * <p>A comparator for evaluating attributes in the
     * <code>AttributeValueList</code>. For example, equals, greater than, less than,
     * etc.</p> <p>The following comparison operators are available:</p> <p> <code>EQ |
     * NE | LE | LT | GE | GT | NOT_NULL | NULL | CONTAINS | NOT_CONTAINS | BEGINS_WITH
     * | IN | BETWEEN</code> </p> <p>The following are descriptions of each comparison
     * operator.</p> <ul> <li> <p> <code>EQ</code> : Equal. <code>EQ</code> is
     * supported for all data types, including lists and maps.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, Binary, String Set, Number Set, or Binary Set.
     * If an item contains an <code>AttributeValue</code> element of a different type
     * than the one provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not equal <code>{"NS":["6", "2", "1"]}</code>.</p>
     * <p/> </li> <li> <p> <code>NE</code> : Not equal. <code>NE</code> is supported
     * for all data types, including lists and maps.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * of type String, Number, Binary, String Set, Number Set, or Binary Set. If an
     * item contains an <code>AttributeValue</code> of a different type than the one
     * provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not equal <code>{"NS":["6", "2", "1"]}</code>.</p>
     * <p/> </li> <li> <p> <code>LE</code> : Less than or equal. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If an item contains
     * an <code>AttributeValue</code> element of a different type than the one provided
     * in the request, the value does not match. For example, <code>{"S":"6"}</code>
     * does not equal <code>{"N":"6"}</code>. Also, <code>{"N":"6"}</code> does not
     * compare to <code>{"NS":["6", "2", "1"]}</code>.</p> <p/> </li> <li> <p>
     * <code>LT</code> : Less than. </p> <p> <code>AttributeValueList</code> can
     * contain only one <code>AttributeValue</code> of type String, Number, or Binary
     * (not a set type). If an item contains an <code>AttributeValue</code> element of
     * a different type than the one provided in the request, the value does not match.
     * For example, <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2",
     * "1"]}</code>.</p> <p/> </li> <li> <p> <code>GE</code> : Greater than or equal.
     * </p> <p> <code>AttributeValueList</code> can contain only one
     * <code>AttributeValue</code> element of type String, Number, or Binary (not a set
     * type). If an item contains an <code>AttributeValue</code> element of a different
     * type than the one provided in the request, the value does not match. For
     * example, <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2",
     * "1"]}</code>.</p> <p/> </li> <li> <p> <code>GT</code> : Greater than. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If an item contains
     * an <code>AttributeValue</code> element of a different type than the one provided
     * in the request, the value does not match. For example, <code>{"S":"6"}</code>
     * does not equal <code>{"N":"6"}</code>. Also, <code>{"N":"6"}</code> does not
     * compare to <code>{"NS":["6", "2", "1"]}</code>.</p> <p/> </li> <li> <p>
     * <code>NOT_NULL</code> : The attribute exists. <code>NOT_NULL</code> is supported
     * for all data types, including lists and maps.</p>  <p>This operator tests
     * for the existence of an attribute, not its data type. If the data type of
     * attribute "<code>a</code>" is null, and you evaluate it using
     * <code>NOT_NULL</code>, the result is a Boolean <code>true</code>. This result is
     * because the attribute "<code>a</code>" exists; its data type is not relevant to
     * the <code>NOT_NULL</code> comparison operator.</p>  </li> <li> <p>
     * <code>NULL</code> : The attribute does not exist. <code>NULL</code> is supported
     * for all data types, including lists and maps.</p>  <p>This operator tests
     * for the nonexistence of an attribute, not its data type. If the data type of
     * attribute "<code>a</code>" is null, and you evaluate it using <code>NULL</code>,
     * the result is a Boolean <code>false</code>. This is because the attribute
     * "<code>a</code>" exists; its data type is not relevant to the <code>NULL</code>
     * comparison operator.</p>  </li> <li> <p> <code>CONTAINS</code> : Checks
     * for a subsequence, or value in a set.</p> <p> <code>AttributeValueList</code>
     * can contain only one <code>AttributeValue</code> element of type String, Number,
     * or Binary (not a set type). If the target attribute of the comparison is of type
     * String, then the operator checks for a substring match. If the target attribute
     * of the comparison is of type Binary, then the operator looks for a subsequence
     * of the target that matches the input. If the target attribute of the comparison
     * is a set ("<code>SS</code>", "<code>NS</code>", or "<code>BS</code>"), then the
     * operator evaluates to true if it finds an exact match with any member of the
     * set.</p> <p>CONTAINS is supported for lists: When evaluating "<code>a CONTAINS
     * b</code>", "<code>a</code>" can be a list; however, "<code>b</code>" cannot be a
     * set, a map, or a list.</p> </li> <li> <p> <code>NOT_CONTAINS</code> : Checks for
     * absence of a subsequence, or absence of a value in a set.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If the target
     * attribute of the comparison is a String, then the operator checks for the
     * absence of a substring match. If the target attribute of the comparison is
     * Binary, then the operator checks for the absence of a subsequence of the target
     * that matches the input. If the target attribute of the comparison is a set
     * ("<code>SS</code>", "<code>NS</code>", or "<code>BS</code>"), then the operator
     * evaluates to true if it <i>does not</i> find an exact match with any member of
     * the set.</p> <p>NOT_CONTAINS is supported for lists: When evaluating "<code>a
     * NOT CONTAINS b</code>", "<code>a</code>" can be a list; however,
     * "<code>b</code>" cannot be a set, a map, or a list.</p> </li> <li> <p>
     * <code>BEGINS_WITH</code> : Checks for a prefix. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * of type String or Binary (not a Number or a set type). The target attribute of
     * the comparison must be of type String or Binary (not a Number or a set
     * type).</p> <p/> </li> <li> <p> <code>IN</code> : Checks for matching elements in
     * a list.</p> <p> <code>AttributeValueList</code> can contain one or more
     * <code>AttributeValue</code> elements of type String, Number, or Binary. These
     * attributes are compared against an existing attribute of an item. If any
     * elements of the input are equal to the item attribute, the expression evaluates
     * to true.</p> </li> <li> <p> <code>BETWEEN</code> : Greater than or equal to the
     * first value, and less than or equal to the second value. </p> <p>
     * <code>AttributeValueList</code> must contain two <code>AttributeValue</code>
     * elements of the same type, either String, Number, or Binary (not a set type). A
     * target attribute matches if the target value is greater than, or equal to, the
     * first element and less than, or equal to, the second element. If an item
     * contains an <code>AttributeValue</code> element of a different type than the one
     * provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not compare to <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2", "1"]}</code>
     * </p> </li> </ul>
     */
    inline ExpectedAttributeValue& WithComparisonOperator(const ComparisonOperator& value) { SetComparisonOperator(value); return *this;}

    /**
     * <p>A comparator for evaluating attributes in the
     * <code>AttributeValueList</code>. For example, equals, greater than, less than,
     * etc.</p> <p>The following comparison operators are available:</p> <p> <code>EQ |
     * NE | LE | LT | GE | GT | NOT_NULL | NULL | CONTAINS | NOT_CONTAINS | BEGINS_WITH
     * | IN | BETWEEN</code> </p> <p>The following are descriptions of each comparison
     * operator.</p> <ul> <li> <p> <code>EQ</code> : Equal. <code>EQ</code> is
     * supported for all data types, including lists and maps.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, Binary, String Set, Number Set, or Binary Set.
     * If an item contains an <code>AttributeValue</code> element of a different type
     * than the one provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not equal <code>{"NS":["6", "2", "1"]}</code>.</p>
     * <p/> </li> <li> <p> <code>NE</code> : Not equal. <code>NE</code> is supported
     * for all data types, including lists and maps.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * of type String, Number, Binary, String Set, Number Set, or Binary Set. If an
     * item contains an <code>AttributeValue</code> of a different type than the one
     * provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not equal <code>{"NS":["6", "2", "1"]}</code>.</p>
     * <p/> </li> <li> <p> <code>LE</code> : Less than or equal. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If an item contains
     * an <code>AttributeValue</code> element of a different type than the one provided
     * in the request, the value does not match. For example, <code>{"S":"6"}</code>
     * does not equal <code>{"N":"6"}</code>. Also, <code>{"N":"6"}</code> does not
     * compare to <code>{"NS":["6", "2", "1"]}</code>.</p> <p/> </li> <li> <p>
     * <code>LT</code> : Less than. </p> <p> <code>AttributeValueList</code> can
     * contain only one <code>AttributeValue</code> of type String, Number, or Binary
     * (not a set type). If an item contains an <code>AttributeValue</code> element of
     * a different type than the one provided in the request, the value does not match.
     * For example, <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2",
     * "1"]}</code>.</p> <p/> </li> <li> <p> <code>GE</code> : Greater than or equal.
     * </p> <p> <code>AttributeValueList</code> can contain only one
     * <code>AttributeValue</code> element of type String, Number, or Binary (not a set
     * type). If an item contains an <code>AttributeValue</code> element of a different
     * type than the one provided in the request, the value does not match. For
     * example, <code>{"S":"6"}</code> does not equal <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2",
     * "1"]}</code>.</p> <p/> </li> <li> <p> <code>GT</code> : Greater than. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If an item contains
     * an <code>AttributeValue</code> element of a different type than the one provided
     * in the request, the value does not match. For example, <code>{"S":"6"}</code>
     * does not equal <code>{"N":"6"}</code>. Also, <code>{"N":"6"}</code> does not
     * compare to <code>{"NS":["6", "2", "1"]}</code>.</p> <p/> </li> <li> <p>
     * <code>NOT_NULL</code> : The attribute exists. <code>NOT_NULL</code> is supported
     * for all data types, including lists and maps.</p>  <p>This operator tests
     * for the existence of an attribute, not its data type. If the data type of
     * attribute "<code>a</code>" is null, and you evaluate it using
     * <code>NOT_NULL</code>, the result is a Boolean <code>true</code>. This result is
     * because the attribute "<code>a</code>" exists; its data type is not relevant to
     * the <code>NOT_NULL</code> comparison operator.</p>  </li> <li> <p>
     * <code>NULL</code> : The attribute does not exist. <code>NULL</code> is supported
     * for all data types, including lists and maps.</p>  <p>This operator tests
     * for the nonexistence of an attribute, not its data type. If the data type of
     * attribute "<code>a</code>" is null, and you evaluate it using <code>NULL</code>,
     * the result is a Boolean <code>false</code>. This is because the attribute
     * "<code>a</code>" exists; its data type is not relevant to the <code>NULL</code>
     * comparison operator.</p>  </li> <li> <p> <code>CONTAINS</code> : Checks
     * for a subsequence, or value in a set.</p> <p> <code>AttributeValueList</code>
     * can contain only one <code>AttributeValue</code> element of type String, Number,
     * or Binary (not a set type). If the target attribute of the comparison is of type
     * String, then the operator checks for a substring match. If the target attribute
     * of the comparison is of type Binary, then the operator looks for a subsequence
     * of the target that matches the input. If the target attribute of the comparison
     * is a set ("<code>SS</code>", "<code>NS</code>", or "<code>BS</code>"), then the
     * operator evaluates to true if it finds an exact match with any member of the
     * set.</p> <p>CONTAINS is supported for lists: When evaluating "<code>a CONTAINS
     * b</code>", "<code>a</code>" can be a list; however, "<code>b</code>" cannot be a
     * set, a map, or a list.</p> </li> <li> <p> <code>NOT_CONTAINS</code> : Checks for
     * absence of a subsequence, or absence of a value in a set.</p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * element of type String, Number, or Binary (not a set type). If the target
     * attribute of the comparison is a String, then the operator checks for the
     * absence of a substring match. If the target attribute of the comparison is
     * Binary, then the operator checks for the absence of a subsequence of the target
     * that matches the input. If the target attribute of the comparison is a set
     * ("<code>SS</code>", "<code>NS</code>", or "<code>BS</code>"), then the operator
     * evaluates to true if it <i>does not</i> find an exact match with any member of
     * the set.</p> <p>NOT_CONTAINS is supported for lists: When evaluating "<code>a
     * NOT CONTAINS b</code>", "<code>a</code>" can be a list; however,
     * "<code>b</code>" cannot be a set, a map, or a list.</p> </li> <li> <p>
     * <code>BEGINS_WITH</code> : Checks for a prefix. </p> <p>
     * <code>AttributeValueList</code> can contain only one <code>AttributeValue</code>
     * of type String or Binary (not a Number or a set type). The target attribute of
     * the comparison must be of type String or Binary (not a Number or a set
     * type).</p> <p/> </li> <li> <p> <code>IN</code> : Checks for matching elements in
     * a list.</p> <p> <code>AttributeValueList</code> can contain one or more
     * <code>AttributeValue</code> elements of type String, Number, or Binary. These
     * attributes are compared against an existing attribute of an item. If any
     * elements of the input are equal to the item attribute, the expression evaluates
     * to true.</p> </li> <li> <p> <code>BETWEEN</code> : Greater than or equal to the
     * first value, and less than or equal to the second value. </p> <p>
     * <code>AttributeValueList</code> must contain two <code>AttributeValue</code>
     * elements of the same type, either String, Number, or Binary (not a set type). A
     * target attribute matches if the target value is greater than, or equal to, the
     * first element and less than, or equal to, the second element. If an item
     * contains an <code>AttributeValue</code> element of a different type than the one
     * provided in the request, the value does not match. For example,
     * <code>{"S":"6"}</code> does not compare to <code>{"N":"6"}</code>. Also,
     * <code>{"N":"6"}</code> does not compare to <code>{"NS":["6", "2", "1"]}</code>
     * </p> </li> </ul>
     */
    inline ExpectedAttributeValue& WithComparisonOperator(ComparisonOperator&& value) { SetComparisonOperator(std::move(value)); return *this;}


    /**
     * <p>One or more values to evaluate against the supplied attribute. The number of
     * values in the list depends on the <code>ComparisonOperator</code> being
     * used.</p> <p>For type Number, value comparisons are numeric.</p> <p>String value
     * comparisons for greater than, equals, or less than are based on ASCII character
     * code values. For example, <code>a</code> is greater than <code>A</code>, and
     * <code>a</code> is greater than <code>B</code>. For a list of code values, see <a
     * href="http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters">http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters</a>.</p>
     * <p>For Binary, DynamoDB treats each byte of the binary data as unsigned when it
     * compares binary values.</p> <p>For information on specifying data types in JSON,
     * see <a
     * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/DataFormat.html">JSON
     * Data Format</a> in the <i>Amazon DynamoDB Developer Guide</i>.</p>
     */
    inline const Aws::Vector<AttributeValue>& GetAttributeValueList() const{ return m_attributeValueList; }

    /**
     * <p>One or more values to evaluate against the supplied attribute. The number of
     * values in the list depends on the <code>ComparisonOperator</code> being
     * used.</p> <p>For type Number, value comparisons are numeric.</p> <p>String value
     * comparisons for greater than, equals, or less than are based on ASCII character
     * code values. For example, <code>a</code> is greater than <code>A</code>, and
     * <code>a</code> is greater than <code>B</code>. For a list of code values, see <a
     * href="http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters">http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters</a>.</p>
     * <p>For Binary, DynamoDB treats each byte of the binary data as unsigned when it
     * compares binary values.</p> <p>For information on specifying data types in JSON,
     * see <a
     * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/DataFormat.html">JSON
     * Data Format</a> in the <i>Amazon DynamoDB Developer Guide</i>.</p>
     */
    inline bool AttributeValueListHasBeenSet() const { return m_attributeValueListHasBeenSet; }

    /**
     * <p>One or more values to evaluate against the supplied attribute. The number of
     * values in the list depends on the <code>ComparisonOperator</code> being
     * used.</p> <p>For type Number, value comparisons are numeric.</p> <p>String value
     * comparisons for greater than, equals, or less than are based on ASCII character
     * code values. For example, <code>a</code> is greater than <code>A</code>, and
     * <code>a</code> is greater than <code>B</code>. For a list of code values, see <a
     * href="http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters">http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters</a>.</p>
     * <p>For Binary, DynamoDB treats each byte of the binary data as unsigned when it
     * compares binary values.</p> <p>For information on specifying data types in JSON,
     * see <a
     * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/DataFormat.html">JSON
     * Data Format</a> in the <i>Amazon DynamoDB Developer Guide</i>.</p>
     */
    inline void SetAttributeValueList(const Aws::Vector<AttributeValue>& value) { m_attributeValueListHasBeenSet = true; m_attributeValueList = value; }

    /**
     * <p>One or more values to evaluate against the supplied attribute. The number of
     * values in the list depends on the <code>ComparisonOperator</code> being
     * used.</p> <p>For type Number, value comparisons are numeric.</p> <p>String value
     * comparisons for greater than, equals, or less than are based on ASCII character
     * code values. For example, <code>a</code> is greater than <code>A</code>, and
     * <code>a</code> is greater than <code>B</code>. For a list of code values, see <a
     * href="http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters">http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters</a>.</p>
     * <p>For Binary, DynamoDB treats each byte of the binary data as unsigned when it
     * compares binary values.</p> <p>For information on specifying data types in JSON,
     * see <a
     * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/DataFormat.html">JSON
     * Data Format</a> in the <i>Amazon DynamoDB Developer Guide</i>.</p>
     */
    inline void SetAttributeValueList(Aws::Vector<AttributeValue>&& value) { m_attributeValueListHasBeenSet = true; m_attributeValueList = std::move(value); }

    /**
     * <p>One or more values to evaluate against the supplied attribute. The number of
     * values in the list depends on the <code>ComparisonOperator</code> being
     * used.</p> <p>For type Number, value comparisons are numeric.</p> <p>String value
     * comparisons for greater than, equals, or less than are based on ASCII character
     * code values. For example, <code>a</code> is greater than <code>A</code>, and
     * <code>a</code> is greater than <code>B</code>. For a list of code values, see <a
     * href="http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters">http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters</a>.</p>
     * <p>For Binary, DynamoDB treats each byte of the binary data as unsigned when it
     * compares binary values.</p> <p>For information on specifying data types in JSON,
     * see <a
     * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/DataFormat.html">JSON
     * Data Format</a> in the <i>Amazon DynamoDB Developer Guide</i>.</p>
     */
    inline ExpectedAttributeValue& WithAttributeValueList(const Aws::Vector<AttributeValue>& value) { SetAttributeValueList(value); return *this;}

    /**
     * <p>One or more values to evaluate against the supplied attribute. The number of
     * values in the list depends on the <code>ComparisonOperator</code> being
     * used.</p> <p>For type Number, value comparisons are numeric.</p> <p>String value
     * comparisons for greater than, equals, or less than are based on ASCII character
     * code values. For example, <code>a</code> is greater than <code>A</code>, and
     * <code>a</code> is greater than <code>B</code>. For a list of code values, see <a
     * href="http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters">http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters</a>.</p>
     * <p>For Binary, DynamoDB treats each byte of the binary data as unsigned when it
     * compares binary values.</p> <p>For information on specifying data types in JSON,
     * see <a
     * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/DataFormat.html">JSON
     * Data Format</a> in the <i>Amazon DynamoDB Developer Guide</i>.</p>
     */
    inline ExpectedAttributeValue& WithAttributeValueList(Aws::Vector<AttributeValue>&& value) { SetAttributeValueList(std::move(value)); return *this;}

    /**
     * <p>One or more values to evaluate against the supplied attribute. The number of
     * values in the list depends on the <code>ComparisonOperator</code> being
     * used.</p> <p>For type Number, value comparisons are numeric.</p> <p>String value
     * comparisons for greater than, equals, or less than are based on ASCII character
     * code values. For example, <code>a</code> is greater than <code>A</code>, and
     * <code>a</code> is greater than <code>B</code>. For a list of code values, see <a
     * href="http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters">http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters</a>.</p>
     * <p>For Binary, DynamoDB treats each byte of the binary data as unsigned when it
     * compares binary values.</p> <p>For information on specifying data types in JSON,
     * see <a
     * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/DataFormat.html">JSON
     * Data Format</a> in the <i>Amazon DynamoDB Developer Guide</i>.</p>
     */
    inline ExpectedAttributeValue& AddAttributeValueList(const AttributeValue& value) { m_attributeValueListHasBeenSet = true; m_attributeValueList.push_back(value); return *this; }

    /**
     * <p>One or more values to evaluate against the supplied attribute. The number of
     * values in the list depends on the <code>ComparisonOperator</code> being
     * used.</p> <p>For type Number, value comparisons are numeric.</p> <p>String value
     * comparisons for greater than, equals, or less than are based on ASCII character
     * code values. For example, <code>a</code> is greater than <code>A</code>, and
     * <code>a</code> is greater than <code>B</code>. For a list of code values, see <a
     * href="http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters">http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters</a>.</p>
     * <p>For Binary, DynamoDB treats each byte of the binary data as unsigned when it
     * compares binary values.</p> <p>For information on specifying data types in JSON,
     * see <a
     * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/DataFormat.html">JSON
     * Data Format</a> in the <i>Amazon DynamoDB Developer Guide</i>.</p>
     */
    inline ExpectedAttributeValue& AddAttributeValueList(AttributeValue&& value) { m_attributeValueListHasBeenSet = true; m_attributeValueList.push_back(std::move(value)); return *this; }

  private:

    AttributeValue m_value;
    bool m_valueHasBeenSet = false;

    bool m_exists;
    bool m_existsHasBeenSet = false;

    ComparisonOperator m_comparisonOperator;
    bool m_comparisonOperatorHasBeenSet = false;

    Aws::Vector<AttributeValue> m_attributeValueList;
    bool m_attributeValueListHasBeenSet = false;
  };

} // namespace Model
} // namespace DynamoDB
} // namespace Aws