IBM SC34-5764-01 - Manual (Page 26)

Components of REXX
The various components of REXX make it a powerful tool for programmers. REXX is made up of:
v Clauses, which can be instructions, null clauses, or labels. Instructions can be:
– Keyword instructions
– Assignments
– Commands (REXX/CICS and CICS commands and SQL).
The language processor processes keyword instructions and assignments.
v Built-in functions — These functions are built into the language processor and provide convenient
processing options.
v External functions — REXX/CICS provides these functions that interact with the system to do specific
tasks for REXX.
v Data stack functions — A data stack can store data for I/O and other types of processing.
Introduction
4 CICS TS for VSE/ESA: REXX Guide