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