&&exists: Difference between revisions
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(Created page with "__TOC__ {| |width="50%"| '''Action:''' |width="50%"| <span class="f_Para">Tests if a macro variable is defined. </span> '''Syntax:'''...") |
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Latest revision as of 19:41, 18 August 2022
Action: |
Tests if a macro variable is defined. Syntax: &&exists(variableName) where variableName is the macro variable whose existence is being checked. If the named variable exists, &&exists returns 1; otherwise, it returns 0. A variable is deemed to "not exist" in these cases:
Examples: The following statement returns 0: echo &&exists("&neverSet") The echo statement below returns 1: set &i = 666 echo &&exists("&i") The echo statement below returns 0: unset &i echo &&exists("&i") |
Introduced: | Build 60 |