Is this documented anywhere?
Yes, in sv.c in the perl source ("use the source, luke" ;-)

Line 1680 ff: 

/*
=for apidoc looks_like_number

Test if the content of an SV looks like a number (or is a number).
C<Inf> and C<Infinity> are treated as numbers (so will not issue a
non-numeric warning), even if your atof() doesn't grok them.

=cut
*/

[download]

and so - suprise! - perlapi tells the same.

Read through sv.c to see what happens. The perl5 spec is coherent with its implementation ;-)

--shmem 

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

In reply to Re: $array[ 'Infinity' ] by shmem
in thread $array[ 'Infinity' ] by Sixtease

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