in reply to Open several files and read line by line

while (<$filename>){
    while (/$id1/g && /$id2/g)
    {
        print "$file:$.\n";
    }
}

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I don't understand. If  /$id1/g && /$id2/g ever becomes true (matching by default against  $_ assigned in the outer while-loop), when will it ever become false? I.e., isn't this an infinite loop? And what's the point of the  /g modifier in these regexes? And yes,  $filename is a terrible name for a file handle!

Update: I should have known. Many thanks, choroba. (But  $filename is still terrible!)

Give a man a fish:  <%-{-{-{-<

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Re^3: Open several files and read line by line
by choroba (Cardinal) on Dec 04, 2015 at 20:51 UTC
    Without /g it would be an infinite loop. But with /g, the matching starts where the last one stopped: 
    $_ = "abcabcabc";
while (/c/g && /a/g) {
    say pos;
}

__END__
Output:
4
7

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    ($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

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