The join of the array leaves $regexpans containing:

/^(big|huge|large)\b/

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It's just a 'generated regex'. I'm not sure why it wasn't written: 

$regexpans = qr/^($regexpans)\b/;

[download]

In reply to Re: what does this regex do? by fishbot_v2
in thread what does this regex do? by moltar512

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