Hello ExReg,

what does ɛ correspond to in our usage?

In formal language theory as applied to regular expressions, ε (epsilon) denotes the empty string. Hence ε corresponds to "" in our (Perl) usage.

See Regular_expression#Formal_definition (which incorrectly, IMO, defines ε as the set containing the empty string) and, more accurately, Empty_string.

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re: Simplifying regexes by Athanasius
in thread Simplifying regexes by ExReg

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