The underscore prototype was introduced in Perl 5.10. In the 2008 node Re: Underscore _ prototype in 5.10, lodin explains it as follows:

The effect of _ is that if the argument is missing, $_ is passed, and thus populates @_.

See the example code there, and also see this blog post.

Hope that helps,

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

In reply to Re: perlsub prototype sub(_) sub foo(_) by Athanasius
in thread perlsub prototype sub(_) sub foo(_) by Anonymous Monk

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