Re: perl syntax oddity

Yitzchak Scott-Thoennes wrote:
 >
> Can anyone give a justification why this should work as it does (or a
> reasonable use):
> 
> $ perl -wle'sub getaglob {*loopvar} for ${&getaglob} (qw/the owl and the pussyc
> at/) { print $loopvar }'

Well, why not?  After all, it works everywhere else:

   sub getaglob {*foo}

   $foo = "beep\n";
   print ${&getaglob};

What's weird is that the more conventional way -- using references -- 
does _not_ work in for() loops:

   sub getaref {\$foo}
   for ${&getaref} (qw/one two three/) {print "$foo\n"}

fails with "Not a GLOB reference".  The other way around it works:

   sub getaref {\$foo}
   for $foo (qw/one two three/) {print "${&getaref}\n"}

I guess it's because for() localizes the variable it's iterating over, 
and needs the glob for that.  Oddly enough, however, local() does not 
accept a glob that way:

   sub getaglob {*foo}
   $foo = "pong\n";
   for ${&getaglob} ("ping ") { print $foo }
   print $foo;

works, printing "ping pong", while:

   sub getaglob {*foo}
   $foo = "pong\n";
   { local ${&getaglob} = "ping "; print $foo }
   print $foo;

fails with "Can't localize through a reference"!

Weird.

-- 
Ilmari Karonen