X-Git-Url: http://git.vpit.fr/?a=blobdiff_plain;f=README;h=bba2ba0abf2a26a97a95b0b3d9f78a1f47250147;hb=ef454c52e92ecd149b3bf0f6e221162cad3955ac;hp=6e144adbf134a68e99aa61b747b519abacab7fe6;hpb=06cb3f3506161a118dc440264dcabcd612b9432c;p=perl%2Fmodules%2FLexical-Types.git

diff --git a/README b/README
index 6e144ad..bba2ba0 100644
--- a/README
+++ b/README
@@ -2,22 +2,36 @@ NAME
     Lexical::Types - Extend the semantics of typed lexicals.
 
 VERSION
-    Version 0.01
+    Version 0.03
 
 SYNOPSIS
+        { package Str; }
+
+        {
+         package My::Types::Str;
+
+         sub new { bless { }, shift }
+        }
+
+        use Lexical::Types as => sub { 'My::Types::' . $_[0] => 'new' };
+
+        my Str $x; # $x is now a My::Types::Str object
+
         {
-         package Str;
+         package My::Types::Int;
 
-         sub TYPEDSCALAR { Some::String::Implementation->new }
+         sub TYPEDSCALAR { bless { }, shift }
         }
 
         use Lexical::Types;
 
-        my Str $x; # $x is now a Some::String::Implementation object
+        use constant Int => 'My::Types::Int';
+
+        my Int $y; # $y is now a My::Types::Int object
 
 DESCRIPTION
-    This module allows you to hook the execution of typed lexicals
-    declarations ("my Foo $x"). In particular, it can be used to
+    This pragma allows you to hook the execution of typed lexicals
+    declarations ("my Str $x"). In particular, it can be used to
     automatically tie or bless typed lexicals.
 
     It is not implemented with a source filter.
@@ -25,38 +39,47 @@ DESCRIPTION
 FUNCTIONS
   "import [ as => [ $prefix | $mangler ] ]"
     Magically called when writing "use Lexical::Types". All the occurences
-    of "my Foo $x" in the current lexical scope will be changed to call at
+    of "my Str $x" in the current lexical scope will be changed to call at
     each run a given method in a given package. The method and package are
-    determined by the parameter "as" :
+    determined by the parameter 'as' :
 
-    *   If it's left unspecified, the "TYPEDSCALAR" method in the "Foo"
+    *   If it's left unspecified, the "TYPEDSCALAR" method in the "Str"
         package will be called.
 
             use Lexical::Types;
             my Str $x; # calls Str->TYPEDSCALAR
 
     *   If a plain scalar $prefix is passed as the value, the "TYPEDSCALAR"
-        method in the "${prefix}::Foo" package will be used.
+        method in the "${prefix}::Str" package will be used.
 
             use Lexical::Types as => 'My::'; # or "as => 'My'"
             my Str $x; # calls My::Str->TYPEDSCALAR
 
     *   If the value given is a code reference $mangler, it will be called
-        at compile-time with arguments 'Foo' and 'TYPEDSCALAR' and is
-        expected to return the desired package and method name (in that
-        order). If any of those is "undef", the default value will be used
-        instead.
+        at compile-time with arguments 'Str' and 'TYPEDSCALAR' and is
+        expected to return :
 
-            use Lexical::Types as => sub { 'My', 'new_' . lc($_[0]) };
-            my Str $x; # the coderef indicates to call My->new_str
+        *   either an empty list, in which case the current typed lexical
+            definition will be skipped (thus it won't be altered to trigger
+            a run-time hook) ;
+
+                use Lexical::Types as => sub { return $_[0] =~ /Str/ ? @_ : () };
+                my Str $y; # calls Str->TYPEDSCALAR
+                my Int $x; # nothing special
+
+        *   or the desired package and method name, in that order (if any of
+            those is "undef", the default value will be used instead).
+
+                use Lexical::Types as => sub { 'My', 'new_' . lc($_[0]) };
+                my Str $x; # the coderef indicates to call My->new_str
 
     The initializer method receives an alias to the pad entry of $x in $_[1]
-    and the original type name ("Foo") in $_[2]. You can either edit $_[1]
+    and the original type name ("Str") in $_[2]. You can either edit $_[1]
     in place, in which case you should return an empty list, or return a new
     scalar that will be copied into $x.
 
   "unimport"
-    Magically called when writing "no Lexical::Types". Turns the module off.
+    Magically called when writing "no Lexical::Types". Turns the pragma off.
 
 INTEGRATION
     You can integrate Lexical::Types in your module so that using it will
@@ -83,10 +106,15 @@ INTEGRATION
         sub new_int { ... }
 
 CAVEATS
-    For "perl" to be able to parse "my Foo $x", the package "Foo" must be
-    defined somewhere, and this even if you use the "as" option to redirect
-    to another package. It's unlikely to find a workaround, as this happens
-    deep inside the lexer, far from the reach of an extension.
+    For "perl" to be able to parse "my Str $x", you need :
+
+    *   either the "Str" package to be defined ;
+
+    *   or for "Str" to be a constant sub returning a valid defined package.
+
+    Those restrictions apply even if you use the 'as' option to redirect to
+    another package, and are unlikely to find a workaround as this happens
+    deep inside the lexer - far from the reach of an extension.
 
     Only one mangler or prefix can be in use at the same time in a given
     scope.
@@ -116,9 +144,14 @@ SUPPORT
 
         perldoc Lexical::Types
 
+    Tests code coverage report is available at
+    <http://www.profvince.com/perl/cover/Lexical-Types>.
+
 ACKNOWLEDGEMENTS
     Inspired by Ricardo Signes.
 
+    Thanks Florian Ragwitz for suggesting the use of constants for types.
+
 COPYRIGHT & LICENSE
     Copyright 2009 Vincent Pit, all rights reserved.