21.4.4 Looping

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There is no support in M4 for doing traditional iterations (ie. `for-do' loops ), however macros may invoke themselves . Thus, it is possible to iterate using recursion. The recursive definition can use conditionals (21.4.3 Conditionals) to terminate the loop at its completion by providing a trivial case. The GNU M4 manual provides some clever recursive definitions, including a definition for a forloop macro that emulates a `for-do' loop.

It is conceivable that you might wish to use these M4 constructs when writing macros to generate large amounts of in-line shell code or arbitrarily nested if; then; fi statements.


This document was generated by Gary V. Vaughan on May, 24 2001 using texi2html


GNU Autoconf, Automake and Libtool
GNU Autoconf, Automake, and Libtool
ISBN: 1578701902
EAN: 2147483647
Year: 2002
Pages: 290

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