Update VPIT::TestHelpers to 15e8aee3

[perl/modules/Sub-Prototype-Util.git] / README

diff --git a/README b/README
index 20b9d5904e2d17b8ef5ae8a766d2e0f430cc3a30..ad69e34840c8e265741c6352da03ecbb056a2bcb 100644 (file)
--- a/README
+++ b/README
@@ -1,57 +1,126 @@
 NAME
 NAME

-    Sub::Prototype::Util - Prototypes-related utility routines.
+    Sub::Prototype::Util - Prototype-related utility routines.

 
 VERSION
 
 VERSION

-    Version 0.01
+    Version 0.11

 
 SYNOPSIS
 
 SYNOPSIS

-        use Sub::Prototype::Util qw/flatten recall/;
+        use Sub::Prototype::Util qw<flatten wrap recall>;

 
 

-        my @a = qw/a b c/;
+        my @a = qw<a b c>;

         my @args = ( \@a, 1, { d => 2 }, undef, 3 );
 
         my @args = ( \@a, 1, { d => 2 }, undef, 3 );
 

-        my @flat = flatten '\@$;$', @args; # ('a', 'b', 'c', 1, { d => 2 })
-        recall 'CORE::push', @args; # @a contains 'a', 'b', 'c', 1, { d => 2 }, undef, 3
+        my @flat = flatten '\@$;$', @args;
+        # @flat contains now ('a', 'b', 'c', 1, { d => 2 })
+
+        my $res = recall 'CORE::push', @args;
+        # @a contains now 'a', 'b', 'c', 1, { d => 2 }, undef, 3
+        # and $res is 7
+
+        my $splice = wrap 'CORE::splice';
+        my @b = $splice->(\@a, 4, 2);
+        # @a contains now ('a', 'b', 'c', 1, 3)
+        # and @b is ({ d => 2 }, undef)

 
 DESCRIPTION
     Prototypes are evil, but sometimes you just have to bear with them,
     especially when messing with core functions. This module provides
 
 DESCRIPTION
     Prototypes are evil, but sometimes you just have to bear with them,
     especially when messing with core functions. This module provides

-    several utilities aimed at faciliting "overloading" of prototyped
+    several utilities aimed at facilitating "overloading" of prototyped

     functions.
 
     They all handle 5.10's "_" prototype.
 
 FUNCTIONS
     functions.
 
     They all handle 5.10's "_" prototype.
 
 FUNCTIONS

-  "flatten $proto, @args"
+  "flatten"
+        my @flattened = flatten($proto, @args);
+

     Flattens the array @args according to the prototype $proto. When @args
     is what @_ is after calling a subroutine with prototype $proto,
     "flatten" returns the list of what @_ would have been if there were no
     Flattens the array @args according to the prototype $proto. When @args
     is what @_ is after calling a subroutine with prototype $proto,
     "flatten" returns the list of what @_ would have been if there were no

-    prototype.
+    prototype. It croaks if the arguments can't possibly match the required
+    prototype, e.g. when a reference type is wrong or when not enough
+    elements were provided.
+
+  "wrap"
+        my $wrapper = wrap($name, %opts);
+        my $wrapper = wrap({ $name => $proto }, %opts);
+
+    Generates a wrapper that calls the function $name with a prototyped
+    argument list. That is, the wrapper's arguments should be what @_ is
+    when you define a subroutine with the same prototype as $name.
+
+        my $a = [ 0 .. 2 ];
+        my $push = wrap 'CORE::push';
+        $push->($a, 3, 4); # returns 3 + 2 = 5 and $a now contains 0 .. 4
+
+    You can force the use of a specific prototype. In this case, $name must
+    be a hash reference that holds exactly one key / value pair, the key
+    being the function name and the value the prototpye that should be used
+    to call it.
+
+        my $push = wrap { 'CORE::push' => '\@$' }; # only pushes 1 arg
+
+    The remaining arguments %opts are treated as key / value pairs that are
+    meant to tune the code generated by "wrap". Valid keys are :
+
+    *   "ref => $func"
+
+        Specifies the function used in the generated code to test the
+        reference type of scalars. Defaults to 'ref'. You may also want to
+        use "reftype" in Scalar::Util.
+
+    *   "wrong_ref => $code"
+
+        The code executed when a reference of incorrect type is encountered.
+        The result of this snippet is also the result of the generated code,
+        hence it defaults to 'undef'. It's a good place to "croak" or "die"
+        too.
+
+    *   "sub => $bool"
+
+        Encloses the code into a "sub { }" block. Default is true.
+
+    *   "compile => $bool"
+
+        Makes "wrap" compile the code generated and return the resulting
+        code reference. Be careful that in this case "ref" must be a fully
+        qualified function name. Defaults to true, but turned off when "sub"
+        is false.
+
+    For example, this allows you to recall into "CORE::grep" and "CORE::map"
+    by using the "\&@" prototype :
+
+        my $grep = wrap { 'CORE::grep' => '\&@' };
+        # the prototypes are intentionally different
+        sub mygrep (&@) { $grep->(@_) }
+
+  "recall"
+        my @res = recall($name, @args);
+        my @res = recall({ $name => $proto }, @args);

 
 

-  "recall $name, @args"

     Calls the function $name with the prototyped argument list @args. That
     Calls the function $name with the prototyped argument list @args. That

-    is, @args should be what @_ is when you define a subroutine with the
-    same prototype as $name. For example,
+    is, @args should be what @_ is when you call a subroutine with $name as
+    prototype. You can still force the prototype by passing "{ $name =>
+    $proto }" as the first argument.

 
         my $a = [ ];
 
         my $a = [ ];

-        recall 'CORE::push', $a, 1, 2, 3;
+        recall { 'CORE::push' => '\@$' }, $a, 1, 2, 3; # $a just contains 1

 
 

-    will call "push @$a, 1, 2, 3" and so fill the arrayref $a with "1, 2,
-    3". This is especially needed for core functions because you can't
-    "goto" into them.
+    It's implemented in terms of "wrap", and hence calls "eval" at each run.
+    If you plan to recall several times, consider using "wrap" instead.

 
 EXPORT
 
 EXPORT

-    The functions "flatten" and "recall" are only exported on request,
-    either by providing their name or by the ':consts' and ':all' tags.
+    The functions "flatten", "wrap" and "recall" are only exported on
+    request, either by providing their name or by the ':funcs' and ':all'
+    tags.

 
 DEPENDENCIES
 
 DEPENDENCIES

-    Carp (core module since perl 5), Scalar::Util (since 5.7.3).
+    Carp, Exporter (core modules since perl 5), Scalar::Util (since 5.7.3).

 
 AUTHOR
     Vincent Pit, "<perl at profvince.com>", <http://www.profvince.com>.
 
 
 AUTHOR
     Vincent Pit, "<perl at profvince.com>", <http://www.profvince.com>.
 

-    You can contact me by mail or on #perl @ FreeNode (vincent or
-    Prof_Vince).
+    You can contact me by mail or on "irc.perl.org" (vincent).

 
 BUGS
     Please report any bugs or feature requests to "bug-sub-prototype-util at
 
 BUGS
     Please report any bugs or feature requests to "bug-sub-prototype-util at


@@ -69,7 +138,7 @@ SUPPORT
     <http://www.profvince.com/perl/cover/Sub-Prototype-Util>.
 
 COPYRIGHT & LICENSE
     <http://www.profvince.com/perl/cover/Sub-Prototype-Util>.
 
 COPYRIGHT & LICENSE

-    Copyright 2008 Vincent Pit, all rights reserved.
+    Copyright 2008,2009,2010,2011,2013 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.
 
     This program is free software; you can redistribute it and/or modify it
     under the same terms as Perl itself.