Gonna start with this: 

(?>^.*?)

[download]
simplifies to 
^

[download]

.*? will always starting by attempting to match 0 characters. And the (?>...) prevents it from matching anything else.

(All I have time for now.)

In reply to Re: Possessive sub-pattern with non-greedy content + recursion: WHY does this work?? by ikegami
in thread Possessive sub-pattern with non-greedy content + recursion: WHY does this work?? by Anonymous Monk

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