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Diffstat (limited to 'txr.1')
| -rw-r--r-- | txr.1 | 30 |
1 files changed, 30 insertions, 0 deletions
@@ -10201,6 +10201,36 @@ is if the operator is used to terminate the implicit anonymous block, and is given an argument, which becomes the result value. +.coNP Macros @ while* and @ until* +.synb +.mets (while* < expression << form *) +.mets (until* < expression << form *) +.syne +.desc +The +.code while* +and +.code until* +macros are similar, respectively, to the macros +.code while +and +.codn until . + +They differ in one respect: they begin by evaluating the +.metn form -s +one time unconditionally, without first evaluating +.metn expression . +After this evaluation, the subsequent behavior is +like that of +.code while +or +.codn until . + +Another way to regard the behavior is that that these forms execute +one iteration unconditionally, without evaluating the termination test prior to +the first iteration. Yet another view is that these constructs relocate the +test from the "top of the loop" to the "bottom of the loop". + .coNP Macro @ whilet .synb .mets (whilet ({ sym | >> ( sym << init-form )}+) |