I have some written some code to capture certain parts of a line into three variables. I've written this in two ways. First, I capture the three relevant variables in a single regex. 
my ($chr,$prot,$panel) = /(chr.*?)\s.*urn:lsid:(.*?)\s.*panel:(.*?):/i
+;

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Alternatively, I capture each with separate regexes. 
my ($chr) = /(chr.*?)\s/i;
my ($prot) = /urn:lsid:(.*?)\s/i;
my ($panel) = /panel:(.*?):/i;

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When testing on my source files, I'm seeing the 2nd approach (separate regexes) is much, much faster. Maybe 10x or so, though I lost the benchmarking I did. I don't understand why the 2nd approach should be so much faster.

Can some monk help give me insight into this, and help me understand how to get maximum speed out of regex matching.

-albert

In reply to Regex, capturing variables vs. speed by albert

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