Re: Can you find the name of a variable?

[ikegami]

I know there are other ways to solve the actual problem

Just as simple as your code:

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

    ...
}

but I'm curious if there is a way to know the name of a variable

PadWalker

[JadeNB]

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.

[ikegami]

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.