=head1 DESCRIPTION
-This pragma lets you define a default object against with methods will be called in the current scope when possible. It is enabled by the C<use with \$obj> idiom (note that you must pass a reference to the object). If you C<use with> several times in the current scope, the default object will be the last specified one.
+This pragma lets you define a default object against with methods will be called in the current scope when possible.
+It is enabled by the C<use with \$obj> idiom (note that you must pass a reference to the object).
+If you C<use with> several times in the current scope, the default object will be the last specified one.
=cut
The main problem to address is that lexical scoping and source modification can only occur at compile time, while object creation and method resolution happen at run-time.
-The C<use with \$obj> statement stores an address to the variable C<$obj> in the C<with> field of the hints hash C<%^H>. It also starts a source filter that replaces function calls with calls to C<with::defer>, passing the name of the original function as the first argument. When the replaced function has a prototype or is part of the core, the call is deferred to a corresponding wrapper generated in the C<with> namespace. Some keywords that couldn't possibly be replaced are also completely skipped. C<no with> undefines the hint and deletes the source filter, stopping any subsequent modification in the current scope.
+The C<use with \$obj> statement stores an address to the variable C<$obj> in the C<with> field of the hints hash C<%^H>.
+It also starts a source filter that replaces function calls with calls to C<with::defer>, passing the name of the original function as the first argument.
+When the replaced function has a prototype or is part of the core, the call is deferred to a corresponding wrapper generated in the C<with> namespace.
+Some keywords that couldn't possibly be replaced are also completely skipped.
+C<no with> undefines the hint and deletes the source filter, stopping any subsequent modification in the current scope.
-When the script is executed, deferred calls first fetch the default object back from the address stored into the hint. If the object C<< ->can >> the original function name, a method call is issued. If not, the calling namespace is inspected for a subroutine with the proper name, and if it's present the program C<goto>s into it. If that fails too, the core function with the same name is recalled if possible, or an "Undefined subroutine" error is thrown.
+When the script is executed, deferred calls first fetch the default object back from the address stored into the hint.
+If the object C<< ->can >> the original function name, a method call is issued.
+If not, the calling namespace is inspected for a subroutine with the proper name, and if it's present the program C<goto>s into it.
+If that fails too, the core function with the same name is recalled if possible, or an "Undefined subroutine" error is thrown.
=head1 IGNORED KEYWORDS
=head1 CAVEATS
-Most likely slow. Almost surely non thread-safe. Contains source filters, hence brittle. Messes with the dreadful prototypes. Crazy. Will have bugs.
+Most likely slow.
+Almost surely non thread-safe.
+Contains source filters, hence brittle.
+Messes with the dreadful prototypes.
+Crazy.
+Will have bugs.
Don't put anything on the same line of C<use with \$obj> or C<no with>.
-When there's a function in the caller namespace that has a core function name, and when no method with the same name is present, the ambiguity is resolved in favor of the caller namespace. That's different from the usual perl semantics where C<sub push; push @a, 1> gets resolved to CORE::push.
+When there's a function in the caller namespace that has a core function name, and when no method with the same name is present, the ambiguity is resolved in favor of the caller namespace.
+That's different from the usual perl semantics where C<sub push; push @a, 1> gets resolved to CORE::push.
If a method has the same name as a prototyped function in the caller namespace, and if a called is deferred to the method, it will have its arguments passed by value.
=head1 BUGS
-Please report any bugs or feature requests to C<bug-with at rt.cpan.org>, or through the web interface at L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=with>. 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-with at rt.cpan.org>, or through the web interface at L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=with>.
+I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.
=head1 SUPPORT
projects / perl / modules / with.git / blobdiff