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The best way to return locations of regex?

haha
New User

Dec 19, 2008, 9:00 AM

Post #1 of 4 (1586 views)

The best way to return locations of regex?	Can't Post

Hi folks,

What is the best method to return all locations for pattern matching? e.g. I have m/somename/g, this will give me all occurrences of pattern "somename", but how do I get the locations of the pattern within the string? Thx!

FishMonger
Veteran

Dec 19, 2008, 9:45 AM

Post #2 of 4 (1585 views)

Re: [haha] The best way to return locations of regex? [In reply to]	Can't Post

perldoc -f index

haha
New User

Dec 19, 2008, 9:57 AM

Post #3 of 4 (1583 views)

Re: [FishMonger] The best way to return locations of regex? [In reply to]	Can't Post

Hi, Fish,

Thx! I know what "index" does but it seems it doesn't solve my problem here. I can use regex to find the patterns first, then find their locations with "index". But that requires two scans of the string. This seems a bit suboptimal. Is there any way to scan once and generate the information I want?

KevinR
Veteran

Dec 19, 2008, 10:30 AM

Post #4 of 4 (1581 views)

Re: [haha] The best way to return locations of regex? [In reply to]	Can't Post

Code

$var = 'somenamefoobarsomenametestfoosomefoonamefoosomenametest'; 
push @pos,$-[0] while ($var =~ /somename/g); 
print "@pos";

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