It might be a little more obvious like this:

$b =  'test 100';

%hash = (
        a => ($b =~ /(\d+)/ ? $1 : 0),
        b => ($b =~ /(\w+)/ ? 1  : 0),
);

print "$hash{a}\n";

[download]

which prints

test

[download]

So, it did the second pattern match first, and interpreted $1 to be the result of that pattern match. It's the same sort of ambiguity that is found in, say, ($i++)+$i.

In reply to Re: Strange Regex Behavior by quester
in thread Strange Regex Behavior by Manchego

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