Perl treats period as space in string

htmanning has asked for the wisdom of the Perl Monks concerning the following question:

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Re: Perl treats period as space in string by choroba (Cardinal) on Jul 20, 2021 at 20:48 UTC
It's even worse, a dot in a regex matches any character except for a newline. Maybe you just want to do `use feature qw{ fc }; my $phrase = fc 'club.market'; if (-1 != index fc $string, $phrase) { ...` [download] `map{substr$_->[0],$_->[1]\|\|0,1}[\\|\|{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^ARGV,3]`	[reply] [d/l] [select]
Re: Perl treats period as space in string by tybalt89 (Monsignor) on Jul 20, 2021 at 20:14 UTC
`if ($string =~ m/\Q$phrase\E/i){` [download]	[reply] [d/l]
Re^2: Perl treats period as space in string by htmanning (Friar) on Jul 20, 2021 at 20:29 UTC
Thanks!	[reply]
Re^3: Perl treats period as space in string by ikegami (Patriarch) on Jul 22, 2021 at 04:03 UTC
Note that this also matches `fooclub.market`. Not sure if that's what you want. If you want to perform an exact case-insensitive comparison, use `if ($string =~ /^\Q$phrase\E\z/i)` [download] or `use feature qw( fc ); if (fc($string) eq fc($phrase))` [download] The second is probably faster. Seeking work! You can reach me at ikegami@adaelis.com	[reply] [d/l] [select]
Re: Perl treats period as space in string by GrandFather (Saint) on Jul 20, 2021 at 20:59 UTC
The '.' is matching any non-newline character which is what it does in a regular expression when it hasn't been quoted. See Perl regular expression metacharacters. Optimising for fewest key strokes only makes sense transmitting to Pluto or beyond	[reply]
Re: Perl treats period as space in string by AnomalousMonk (Archbishop) on Jul 21, 2021 at 00:57 UTC
... a database of phrases that I'm checking a string against. The technique discussed in haukex's Building Regex Alternations Dynamically article may be helpful in such an application. Give a man a fish: `<%-{-{-{-<`	[reply] [d/l]
Re^2: Perl treats period as space in string by parv (Parson) on Jul 21, 2021 at 01:18 UTC
Today I noticed grex ... grex is a library as well as a command-line utility that is meant to simplify the often complicated and tedious task of creating regular expressions. It does so by automatically generating a single regular expression from user-provided test cases ... This project has started as a Rust port of the JavaScript tool regexgen written by Devon Govett ...	[reply]
Re^3: Perl treats period as space in string by Fletch (Bishop) on Jul 21, 2021 at 05:46 UTC
Similar frak in clojure/cljs which might could be trawled for inspiration as well. The cake is a lie. The cake is a lie. The cake is a lie.	[reply]
Re: Perl treats period as space in string by perlfan (Parson) on Jul 20, 2021 at 22:07 UTC
It's confusing to define the regexp in a variable, then place it there between the `/../`; The reason is that in the assignment it's very much just a string. When you place it in the regexp context, it suddenly means something different (i.e., the "dot"). So don't do that unless it's very cleary you're dynamically defining your regular expression, otherwise you're just making it more confusing for you and anyone else who may be looking at this even in the very near future.	[reply] [d/l]
Re^2: Perl treats period as space in string by BillKSmith (Monsignor) on Jul 21, 2021 at 18:49 UTC
You can solve this problem with `qr` in Regexp Quote Like Operators. `use strict; use warnings; use Test::More tests => 2; my $phrase = qr/club\.market/; unlike( 'club market', $phrase, 'not match space' ); like( 'club.market', $phrase, 'match period' );` [download] RESULT, `1..2 ok 1 - not match space ok 2 - match period` [download] Bill	[reply] [d/l] [select]