=head1 VERSION
-Version 0.06
+Version 0.10
=cut
our $VERSION;
BEGIN {
- $VERSION = '0.06';
+ $VERSION = '0.10';
}
=head1 SYNOPSIS
sub zap {
try {
return @things; # returns to try() and then outside zap()
+ # not reached
}
+ # not reached
}
my @what = zap(); # @what contains @things
=head2 C<reap $callback, $context>
-Add a destructor that calls C<$callback> when the upper scope represented by C<$context> ends.
+Add a destructor that calls C<$callback> (in void context) when the upper scope represented by C<$context> ends.
=head2 C<localize $what, $value, $context>
Other sigils (C<'@'>, C<'%'>, C<'&'> and C<'*'>) require C<$value> to be a reference of the corresponding type.
When the symbol is given by a string, it is resolved when the actual localization takes place and not when C<localize> is called.
-This means that
+Thus, if the symbol name is not qualified, it will refer to the variable in the package where the localization actually takes place and not in the one where the C<localize> call was compiled.
+For example,
+
+ {
+ package Scope;
+ sub new { localize '$tag', $_[0] => UP }
+ }
+
+ {
+ package Tool;
+ {
+ Scope->new;
+ ...
+ }
+ }
- sub tag { localize '$x', $_[0] => UP }
+will localize C<$Tool::tag> and not C<$Scope::tag>.
-will localize in the caller's namespace.
+Note that if C<$what> is a string denoting a variable that wasn't declared beforehand, the relevant slot will be vivified as needed and won't be deleted from the glob when the localization ends.
+This situation never arises with C<local> because it only compiles when the localized variable is already declared.
+Although I believe it shouldn't be a problem as glob slots definedness is pretty much an implementation detail, this behaviour may change in the future if proved harmful.
=back
If C<$what> is a glob, the slot to fill is determined from which type of reference C<$value> is ; otherwise it's inferred from the sigil.
C<$key> is either an array index or a hash key, depending of which kind of variable you localize.
+Just like for L</localize>, when C<$what> is a string pointing to an undeclared variable, it will be vivified but the variable itself will be empty when the localization ends (although it will still exist in its parent glob).
+
=head2 C<localize_delete $what, $key, $context>
Similiar to L</localize>, but for deleting variables or array/hash elements.
my $num = sub {
my @a = ('a' .. 'z');
unwind @a => HERE;
+ # not reached
}->();
will set C<$num> to C<'z'>.
my $num = sub {
my @a = ('a' .. 'z');
unwind +(want_at(HERE) ? @a : scalar @a) => HERE;
+ # not reached
}->();
-will righteously set C<$num> to C<26>.
+will rightfully set C<$num> to C<26>.
+
+=head1 CONSTANTS
+
+=head2 C<SU_THREADSAFE>
+
+True iff the module could have been built when thread-safety features.
=head1 WORDS
The functions L</reap>, L</localize>, L</localize_elem>, L</localize_delete>, L</unwind> and L</want_at> are only exported on request, either individually or by the tags C<':funcs'> and C<':all'>.
+The constant L</SU_THREADSAFE> is also only exported on request, individually or by the tags C<':consts'> and C<':all'>.
+
Same goes for the words L</TOP>, L</HERE>, L</UP>, L</SUB>, L</EVAL>, L</SCOPE> and L</CALLER> that are only exported on request, individually or by the tags C<':words'> and C<':all'>.
=cut
our @EXPORT = ();
our %EXPORT_TAGS = (
- funcs => [ qw/reap localize localize_elem localize_delete unwind want_at/ ],
- words => [ qw/TOP HERE UP SUB EVAL SCOPE CALLER/ ],
+ funcs => [ qw/reap localize localize_elem localize_delete unwind want_at/ ],
+ words => [ qw/TOP HERE UP SUB EVAL SCOPE CALLER/ ],
+ consts => [ qw/SU_THREADSAFE/ ],
);
our @EXPORT_OK = map { @$_ } values %EXPORT_TAGS;
$EXPORT_TAGS{'all'} = [ @EXPORT_OK ];
L<Alias>, L<Hook::Scope>, L<Scope::Guard>, L<Guard>.
+L<Continuation::Escape> is a thin wrapper around L<Scope::Upper> that gives you a continuation passing style interface to L</unwind>.
+It's easier to use, but it requires you to have control over the scope where you want to return.
+
=head1 AUTHOR
Vincent Pit, C<< <perl at profvince.com> >>, L<http://www.profvince.com>.
=head1 BUGS
-Please report any bugs or feature requests to C<bug-scope-upper at rt.cpan.org>, or through the web interface at L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Scope-Upper>. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.
+Please report any bugs or feature requests to C<bug-scope-upper at rt.cpan.org>, or through the web interface at L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Scope-Upper>.
+I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.
=head1 SUPPORT
=head1 COPYRIGHT & LICENSE
-Copyright 2008-2009 Vincent Pit, all rights reserved.
+Copyright 2008,2009,2010 Vincent Pit, all rights reserved.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
projects / perl / modules / Scope-Upper.git / blobdiff