NAME¶
End - generalized END {}.
SYNOPSIS¶
use End;
{ my $foo = end {print "Leaving the block\n"};
...
last; # prints "Leaving the block\n".
...
}
DESCRIPTION¶
The module "End" exports a single subroutine "end", which
allows you to set up some code that is run whenever the current block is
exited, regardless whether that is due to a "return",
"next", "last", "redo", "exit",
"die", "goto" or just reaching the end of the block.
To be more precise, "end" returns an object, that will execute the
code when the object is destroyed; that is, when the variable assigned to goes
out of scope. If the variable is lexical to the current block, the code will
be executed when leaving the block.
One can force premature execution of the code by undefining the variable
assigned to, or assigning another value to the variable.
"end" only takes one argument, a code reference. If one wishes the
code reference to take arguments, wrapping the code reference in a closure
suffices.
BUGS¶
Due to a bug in Perl 5.6.0 (and perhaps before), anonymous subroutines that are
not a closure will not go out of scope, not even on program termination. That
is why "end" wraps the code fragment in a closure.
There is a second bug in Perl 5.6.0 (and perhaps before) why this is necessary.
If the code fragment isn't wrapped in another code reference, the original
subroutine will be blessed in the package, making that "ref" on that
code no longer returns the right value.
DEVELOPMENT¶
The current sources of this module are found on github,
<
git://github.com/Abigail/end.git>.
AUTHOR¶
This package was written by Abigail, <mailto:cpan@abigail.be>
COPYRIGHT & LICENSE¶
Copyright (C) 2000 - 2009, Abigail
Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"),
to deal in the Software without restriction, including without limitation the
rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
sell copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO
EVENT SHALL THE AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.