Re: Use of Typeglob

Answer to udpated question:

When used as a file handle:

Pro: Lexicals can't be localized (but they can be block scoped).
Con: Typeglobs can't be blocked scoped (but they can be localized).
Pro: open LEXICAL, ... requires 5.6 or greater.
Con: The name isn't checked at run-time, so typos are harder to find. However, you will get a compile-time warning if the typo isn't repeated or pasted. For example,
perl -Mstrict -w -e "my $fh = *STDOOUT; print $fh 'moo'"

When used as a tied file handle:

I think you have no choice but to use a typeglob if you want a tied file handle.

When used to alias function:

When used to alias other things:

Comment on Re: Use of Typeglob Select or Download Code

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Re^2: Use of Typeglob by ysth (Canon) on Aug 11, 2005 at 09:50 UTC
When used as a tied file handle: I think you have no choice but to use a typeglob if you want a tied file handle. As of 5.8.0, filehandle ties are attached to the IO handle, not the typeglob, so you can tie even globless lexical filehandles: `use Tie::Handle; use Symbol "geniosym"; my $fh = geniosym; tie $fh, "Tie::StdHandle" or die; print tied($fh);` [download] The * is required only to let tie/tied know you want a filehandle tie, not a scalar tie; no actual typeglobs are used, except temporarily.	[reply] [d/l]

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Re^2: Use of Typeglob
by ysth (Canon) on Aug 11, 2005 at 09:50 UTC

When used as a tied file handle:
I think you have no choice but to use a typeglob if you want a tied file handle.

use Tie::Handle;
use Symbol "geniosym";
my $fh = geniosym;
tie *$fh, "Tie::StdHandle" or die;
print tied(*$fh);
[download]