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How to find which comes first: ' " ', '(', or ')'?

by Anonymous Monk
on Oct 17, 2000 at 07:40 UTC ( #37089=categorized question: print w/replies, xml ) Need Help??
Contributed by Anonymous Monk on Oct 17, 2000 at 07:40 UTC
Q&A  > strings


I have a string, and I want to find which one of the following 3 characters come first (ie, is on the left-most side of a given string) ?

for example:

qwert(ui)" should return ( qwerty"(ff) should return " qwer)()(" should return )
and so on.


Answer: How to find which comes first: '"', '(', or ')'?
contributed by merlyn

my ($first) = $string =~ /(["()])/;
<Editor's Note>
From perlop:
If the `/g' option is not used, `m//' in list context returns a list consisting of the subexpressions matched by the parentheses in the pattern, i.e., (`$1', `$2', `$3'...).

if ( ($F1, $F2, $Etc) = ($foo =~ /^(\S+)\s+(\S+)\s*(.*)/) )

So, by parenthesizing the character class containing the characters you want to find, the regex will return that character when matched.

The parentheses around the left-hand-side variable (here, $first) are required, to put the expression in list context. In scalar context, a regex will only return true or false.
</Editor's Note>

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