Re: [perlre] using qr

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Re: Re: [perlre] using qr - help needed by broquaint (Abbot) on Nov 08, 2002 at 15:19 UTC
Because `qr` compiles the regex it makes the `/o` modifier rather superfluous. It does however apply to situations where you have a match which has a variable in it and you only want it to be compiled once e.g `my $match = shift @ARGV; my @matched = grep /^$match$/o, <>;` [download] So there the regex will only be compiled once instead for each iteration within the `grep`. See the `perlop\|perlop manpage` for more info. HTH `_________ broquaint`	[reply] [d/l]
Re^3: [perlre] using qr - help needed by Aristotle (Chancellor) on Nov 08, 2002 at 19:01 UTC
That can be done with `qr//` as well though. `my $rx = qr/^@{[shift @ARGV]}$/; my @match = grep /$rx/, <>;` [download] `qr//` also is much less likely to be used mistakenly than `/o` and much easier to spot when it is. `/o` should be considered a relic from pre-`qr//` times that has few if any uses anymore. Makeshifts last the longest.	[reply] [d/l]