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Re^2: Defining substring matches

by AnomalousMonk (Abbot)
on Sep 21, 2013 at 14:32 UTC ( #1055129=note: print w/ replies, xml ) Need Help??

in reply to Re: Defining substring matches
in thread Defining substring matches

while( $seq =~ m[($re)]g ) { printf "Found: '$1' at '$id':%d\n", $-[0]; }

A question of idle (and perhaps rather trivial) curiosity: In the quoted code, you use  $-[0] "offset of the start of the last successful match" (see  @- in perlvar). My reflexive choice would have been  $-[1] since capture group 1 is being matched. There's no difference in the behavior of the code since capture group 1 is all that's matched, but was there a particular reason you chose as you did?

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Re^3: Defining substring matches
by BrowserUk (Pope) on Sep 21, 2013 at 15:22 UTC

    Um. I cannot remember ever using indexes above 0 with @- or @+. I'm sure I probably have at some point, but I don't remember doing so.

    When I first typed it, I didn't use capture brackets and only printed the id and position. I added the capture brackets and '$1' as an afterthought.

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