Greetings, Monks.

I was skimming my older nodes and came across this reply, which says: 

qw(foo bar))[$_[0]] 
would still yield 'foo' when @_ is empty (therefore, $_[0] is undef).

[download]

What I'm wondering, is if that's a numeric constant thing? If @_ is empty, does the array usage of [] force the undefined $_[0] into numeric context, which would make is a 0? Is that how that works? I did some tests, such as: 

Enter h or `h h' for help, or `man perldebug' for more help.

h
main::(-:1):    h
  DB<1> x $ARGV[0]
0  undef
  DB<2> x 3 + $ARGV[0]
0  3
  DB<3> x 3 * $ARGV[0]
0  0

[download]
which is what I was expecting, thinking that an undef would be forced into a numeric 0 because of arithmetic operands. So, I'm pretty sure that's what's happening, but that's just an educated guess. Am I right?

Thanks.

--

Mephit (See my home node for my rant about Opera and PerlMonks, and my earliest nodes.

In reply to Is this a numeric context thing? by mephit

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