SAP NAMES ESCAPING documentation, setup help and example usage

ARTICLE

Escape Character for Names
The character ! can be written directly before a name in order to distinguish it from an ABAP word with the same name in a statement. With the exception of the first word, each word of a statement that is preceded by the escape character is interpreted as an operand, and not as an ABAP word, when the program is generated. The escape character itself is not part of a name and is ignored when the statement is executed.

Note
The escape character may be required on rare occasions in which the compiler cannot tell the difference between an operand and a reserved word of the same name. Otherwise, it can be used for the documentation of operands in the source code.

Example
Without the escape character ! before CHANGING after
USING , the following program extract would have incorrect syntax, because a formal parameter must be entered after USING . Although the second escape character is not necessary, it serves to document
USING after CHANGING as a formal parameter.
FORM test USING !CHANGING
CHANGING !USING.
using = changing.
ENDFORM.

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