-- | One or more substitution tokens for attribute names in an expression. The
-- following are some use cases for using /ExpressionAttributeNames/:
--
-- To access an attribute whose name conflicts with a DynamoDB reserved word.
--
-- To create a placeholder for repeating occurrences of an attribute name in
-- an expression.
--
-- To prevent special characters in an attribute name from being
-- misinterpreted in an expression.
--
-- Use the # character in an expression to dereference an attribute name. For
-- example, consider the following attribute name:
--
-- 'Percentile'
--
-- The name of this attribute conflicts with a reserved word, so it cannot be
-- used directly in an expression. (For the complete list of reserved words, go
-- to <http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ReservedWords.html Reserved Words> in the /Amazon DynamoDB Developer Guide/). To work around
-- this, you could specify the following for /ExpressionAttributeNames/:
--
-- '{"#P":"Percentile"}'
--
-- You could then use this substitution in an expression, as in this example:
--
-- '#P = :val'
--
-- Tokens that begin with the : character are /expression attribute values/,
-- which are placeholders for the actual value at runtime.
--
-- For more information on expression attribute names, go to <http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html Accessing ItemAttributes> in the /Amazon DynamoDB Developer Guide/.
giExpressionAttributeNames :: Lens' GetItem (HashMap Text Text)
giExpressionAttributeNames =
    lens _giExpressionAttributeNames
        (\s a -> s { _giExpressionAttributeNames = a })
            . _Map
giExpressionAttributeNames :: Lens' GetItem (HashMap Text Text)
giExpressionAttributeNames =
    lens _giExpressionAttributeNames
        (\s a -> s { _giExpressionAttributeNames = a })
            . _Map
giExpressionAttributeNames =
    lens _giExpressionAttributeNames
        (\s a -> s { _giExpressionAttributeNames = a })
            . _Map