Re: Negate a regular expression

Chad Perrin wrote:
On Fri, Dec 29, 2006 at 11:36:25PM -0500, Mathew Snyder wrote:
I'm trying to set up an if clause to exit if an answer given is anything but
either any case combination of 'y' or 'yes'. This is what I have:

exit if $ans =~ m/[^y|^yes]/i;

Will that do what I want?

If you want anything but a given pattern, the best way to do it is
usually by using the !~ operator. Thus, if you have a pattern $foo,
this matches that pattern:

exit if $ans =~ m/$foo/i;

. . . while this matches anything but that pattern:

exit if $ans !~ m/$foo/i;


Thanks. That looks like exactly what I was looking for.

Mathew
.

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