Why do these two snippets print different things? ($1 vs $_, for the impatient):

perl -e '$a="1b2cde5";for($a=~/(\d+)/g){$t+=$1;};print "$t\n";'
perl -e '$a="1b2cde5";for($a=~/(\d+)/g){$t+=$_;};print "$t\n";'

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The first one prints 15. The second one prints 8.

My confusion is with the first one. I can understand it's taking the rightmost match, but in that case why does the loop iterate three times? I would have thought if the loop iterated three times, it would put different values into $1 each time. I'm trying to understand this one. Any explanations appreciated. This is perl 5.8.4.

In reply to Looping on a match, and value of $1 by dmorgo

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