I know I'm gonna feel like an idiot when I read the explaination of this but...what the hey.

I was playing around with regexes to match MAC addresses as formatted in a recent SoPW and tried this. 

print $mac =~ 
/^([0-9A-Z]{1,2}):([0-9A-Z]{1,2}):([0-9A-Z]{1,2}):([0-9A-Z]{1,2}):([0-
+9A-Z]{1,2}):([0-9A-Z]{1,2})$/
0 0A 0C B B8 F

[download]

Works fine, but the obvious step is to reduce the repeating elements by grouping and adding a repeat count. So I tried this 

print $mac =~ /^(?:([0-9A-Z]{1,2}):){5}([0-9A-Z]{1,2})$/
B8 F

[download]

Which wasn't what I expected at all. So I tried this 

print $mac =~ /^(?:([0-9A-Z]{1,2}):){2}([0-9A-Z]{1,2}):([0-9A-Z]{1,2})
+:([0-9A-Z]{1,2}):([0-9A-Z]{1,2})$/
0A 0C B B8 F

[download]

Which seems to indicate that if you have a capturing group within a repeat group, that whilst the number of repetitions is honoured and must be consistant with the data, only the last occurance of the capturing group actually captures?

This is contra my expectations, and despite reading the perlre and others, I don't see anything that would indicate this is the case.

Did I miss the relevant passage in the docs and this is working as designed or uncover a bug?

Examine what is said, not who speaks.

The 7th Rule of perl club is -- pearl clubs are easily damaged. Use a diamond club instead.

In reply to Capturing brackets within a repeat group by BrowserUk

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