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Re^2: Can you find the name of a variable?

by JadeNB (Chaplain)
on Nov 15, 2009 at 07:51 UTC ( #807236=note: print w/ replies, xml ) Need Help??


in reply to Re: Can you find the name of a variable?
in thread Can you find the name of a variable?

sub blah { my ($foo, $bar, $baz) = @_; for my $arg (qw( foo bar baz )) { croak("$arg missing/undefined") if !defined(shift); } ... }

I know that I must be missing something here (UPDATE: yup!), but why not just

sub blah { my ( $foo, $bar, $baz ); for my $arg ( ( $foo, $bar, $baz ) = @_ ) { croak "You forgot something" unless defined $arg; } do_something; }
or even something like the List::MoreUtils-flavoured
sub blah { croak "You forgot something" unless all { defined } ( my ( $foo, $ +bar, $baz ) = @_ ); do_something; }
That is, why have the for loop run over the argument list ‘indirectly’ when it's right there to be had?

UPDATE: Indeed, I missed the entirety of the author's point, which was precisely that he wanted more than what his code snippet already did—namely, to detect which, if any, of the relevant variables was already defined.


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Re^3: Can you find the name of a variable?
by ikegami (Pope) on Nov 15, 2009 at 08:44 UTC

    I know that I must be missing something here

    They don't produce the right output. The OP wants to identify which arg is not defined by name.

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