Re: Matching string containing values between 0 and 100 inclusive

perl -MRegexp::Assemble -le 'print Regexp::Assemble->new->add(0..100)->as_string'

...produces...

(?:1(?:[123456789]|0?0)?|2\d?|3\d?|4\d?|5\d?|6\d?|7\d?|8\d?|9\d?|0)

This could be simplified by gathering the 2\d?, 3\d?... subpatterns and factoring them into [2-9]\d?, but that would be less efficient since character classes are slower, and in 5.10 this would bypass demerphq's trie optimisation.

On the plus side, while it will examine all the 10 primary alternatives during a fail, it's failing on EXACT matches, which is fast.

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Re^2: Matching string containing values between 0 and 100 inclusive by ikegami (Patriarch) on Mar 18, 2009 at 13:46 UTC
You should use Regexp::List from the same for distro when you have strings rather than patterns. It doesn't affect the outcome in this case, but let's not get into the habit of using the wrong tool. `perl -MRegexp::List -le'print Regexp::List->new->list2re(0..100)'` [download] in 5.10 this would bypass demerphq's trie optimisation. In 5.10, the equivalent of Regexp::Assemble would be: `my $re = join '\|', 0..100;` [download] and the equivalent of Regexp::List would be: `my $re = join '\|', map quotemeta, 0..100;` [download]	[reply] [d/l] [select]

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Re^2: Matching string containing values between 0 and 100 inclusive
by ikegami (Patriarch) on Mar 18, 2009 at 13:46 UTC

You should use Regexp::List from the same for distro when you have strings rather than patterns. It doesn't affect the outcome in this case, but let's not get into the habit of using the wrong tool.

perl -MRegexp::List -le'print Regexp::List->new->list2re(0..100)'
[download]

in 5.10 this would bypass demerphq's trie optimisation.

In 5.10, the equivalent of Regexp::Assemble would be:

my $re = join '|', 0..100;
[download]

and the equivalent of Regexp::List would be:

my $re = join '|',
         map quotemeta,
         0..100;
[download]

[reply]
[d/l]
[select]