Aborting a module

suaveant has asked for the wisdom of the Perl Monks concerning the following question:

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Re: Aborting a module by almut (Canon) on Oct 23, 2007 at 19:03 UTC
You might want to use the `if` module to make the `use` statements conditional: `use if !$skip, 'Config';` [download]	[reply] [d/l] [select]
Re: Aborting a module (return 1) by tye (Sage) on Oct 23, 2007 at 19:09 UTC
You can `return 1;` from a module and the rest won't be processed. I suspect that would also work from a `BEGIN` block but I'll let you test that. - tye	[reply] [d/l] [select]
Re^2: Aborting a module (return 1) by FunkyMonk (Bishop) on Oct 23, 2007 at 20:17 UTC
I thought that `BEGIN { }` was just magic subroutine, so a return just returns from the BEGIN block. My tests seem to confirm this: `sub BEGIN { print "hello\n"; return 1; } print "bye\n"` [download] prints (wait for it...) `hello bye` [download]	[reply] [d/l] [select]
Re^3: Aborting a module (sub BEGIN) by tye (Sage) on Oct 23, 2007 at 21:06 UTC
Yes, precisely. I should have realized that. Thanks. - tye	[reply]
Re^2: Aborting a module (return 1) by andreas1234567 (Vicar) on Oct 23, 2007 at 20:05 UTC
Like this? It seems to continue past the `BEGIN` block. `$ perl -wl use strict; BEGIN { return 1; } print "foo"; __END__ foo` [download] -- Andreas	[reply] [d/l] [select]
Re^3: Aborting a module (return 1) by tye (Sage) on Oct 23, 2007 at 20:13 UTC
Rereading the root node, the BEGIN was an example of a complicated way of using the module rather than code within the module. So the following should work fine: `package My::Module; if( ... ) { # This module is useless in this case: return 1; } ... 1;` [download] Another possiblity is: `package My::Module; if( ... ) { require My::Module::Internal; } 1;` [download] - tye	[reply] [d/l] [select]
Re^4: Aborting a module (return 1) by suaveant (Parson) on Oct 24, 2007 at 14:40 UTC
Re^3: Aborting a module (return 1) by ikegami (Patriarch) on Oct 23, 2007 at 20:12 UTC
Confirmed, it doesn't work from within `BEGIN`. `>type M.pm package M; BEGIN { return 1; } print "Point A\n"; return 1; print "Point B\n"; 1; >perl -e "use M;" Point A` [download]	[reply] [d/l] [select]
Re^2: Aborting a module (return 1) by suaveant (Parson) on Oct 24, 2007 at 14:34 UTC
Yeah... it's annoying... you can return from the BEGIN block but it doesn't stop anything except the processing of the rest of that BEGIN. Ah well. - Ant - Some of my best work - (1 2 3)	[reply]
Re: Aborting a module by jettero (Monsignor) on Oct 23, 2007 at 18:36 UTC
`BEGIN{ eval "use $packagename"; $package_didnt_work =1 if $@ }` maybe? `if( $something ) { eval "use Something"; }`? -Paul	[reply] [d/l] [select]