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Diffstat (limited to 'doc/case.html')
| -rw-r--r-- | doc/case.html | 44 |
1 files changed, 40 insertions, 4 deletions
diff --git a/doc/case.html b/doc/case.html index 5340c07..a7d2a84 100644 --- a/doc/case.html +++ b/doc/case.html @@ -31,7 +31,7 @@ matches. </p> <pre> - case [ -E | -e | -i | -n ] <em>value</em> + case [ -E | -e ] [ -i ] [ -n | -N ] <em>value</em> { [ regex { <em>prog...</em> } ] [ regex { <em>prog...</em> } ] @@ -50,7 +50,8 @@ in the order they are given. </li> executes into the <em>prog...</em> command line that immediately follows the matched regex. </li> <li> If <em>value</em> matches no <em>regex</em>, <tt>case</tt> -eventually execs into <em>progdefault...</em>. </li> +eventually execs into <em>progdefault...</em>, or exits 0 if <em>progdefault...</em> +is empty. </li> </ul> <h2> Options </h2> @@ -63,10 +64,11 @@ regular expressions</a>. </li> <a href="https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html#tag_09_04">extended regular expressions</a>. This is the default. </li> <li> <tt>-i</tt> : Perform case-insensitive matches. </li> + <li> <tt>-N</tt> : Make the matching expression and +subexpressions available to <em>prog</em>'s environment. See the "Subexpression +matching" section below. </li> <li> <tt>-n</tt> : Do not transmit the matching expression and subexpressions to <em>prog...</em> via the environment. This is the default. </li> - <li> <tt>-N</tt> : Make the matching expression and -subexpressions available to <em>prog</em>'s environment. </li> </ul> <h2> Subexpression matching </h2> @@ -89,5 +91,39 @@ in <em>regex</em>. </li> <a href="elgetpositionals.html">elgetpositionals</a> program. </p> +<h3> An example </h3> + +<p> + Consider the following script; say it's named <tt>match</tt>. +</p> + +<pre>#!/bin/execlineb -S1 +emptyenv +case -N -- $1 +{ + "\\([fo]+\\)bar\\(baz\\)" { /usr/bin/env } +} +</pre> + +<p> + Running <tt>match foooobarbaz</tt> will print the following lines, corresponding +to the output of the <tt>/usr/bin/env</tt> command: +</p> + +<pre>0=\([fo]+\)bar\(baz\) +#=2 +1=foooo +2=baz +</pre> + +<h2> Notes </h2> + +<ul> + <li> <em>value</em> must match <em>regex</em> as a full word. If only a substring of <em>value</em> +matches <em>regex</em>, it is not considered a match. </li> + <li> If <em>value</em> matches no <em>regex</em>, <em>progdefault...</em> is always executed with an +unmodified environment, whether subexpression matching has been requested or not. </li> +</ul> + </body> </html> |