This is 0.21

[perl/modules/indirect.git] / README

diff --git a/README b/README
index efc7130ba9c2bf37cc91fa642f84fcc5852ff653..a563ea0adc3a9a95c73022856fa910878e409c71 100644 (file)
--- a/README
+++ b/README
@@ -2,7 +2,7 @@ NAME
     indirect - Lexically warn about using the indirect object syntax.
 
 VERSION
     indirect - Lexically warn about using the indirect object syntax.
 
 VERSION

-    Version 0.15
+    Version 0.21

 
 SYNOPSIS
         # In a script
 
 SYNOPSIS
         # In a script


@@ -16,6 +16,8 @@ SYNOPSIS
           my $z = new Pineapple 'fresh'; # croaks 'You really wanted Pineapple->new at blurp.pm:13'
          }
         }
           my $z = new Pineapple 'fresh'; # croaks 'You really wanted Pineapple->new at blurp.pm:13'
          }
         }

+        try { ... }; # warns
+

         no indirect ':fatal';
         if (defied $foo) { ... } # croaks, note the typo
 
         no indirect ':fatal';
         if (defied $foo) { ... } # croaks, note the typo
 


@@ -29,15 +31,18 @@ SYNOPSIS
 DESCRIPTION
     When enabled (or disabled as some may prefer to say, since you actually
     turn it on by calling "no indirect"), this pragma warns about indirect
 DESCRIPTION
     When enabled (or disabled as some may prefer to say, since you actually
     turn it on by calling "no indirect"), this pragma warns about indirect

-    object syntax constructs that may have slipped into your code. This
-    syntax is now considered harmful, since its parsing has many quirks and
-    its use is error prone (when "swoosh" isn't defined, "swoosh $x"
-    actually compiles to "$x->swoosh").
+    object syntax constructs that may have slipped into your code.
+
+    This syntax is now considered harmful, since its parsing has many quirks
+    and its use is error prone (when "swoosh" isn't defined, "swoosh $x"
+    actually compiles to "$x->swoosh"). In
+    <http://www.shadowcat.co.uk/blog/matt-s-trout/indirect-but-still-fatal>,
+    Matt S. Trout gives an example of an indirect construct that can cause a
+    particularly bewildering error.

 
 

-    It currently does not warn when the object is enclosed between braces
-    (like "meth { $obj } @args") or for core functions ("print" or "say").
-    This may change in the future, or may be added as optional features that
-    would be enabled by passing options to "unimport".
+    It currently does not warn for core functions ("print", "say", "exec" or
+    "system"). This may change in the future, or may be added as optional
+    features that would be enabled by passing options to "unimport".

 
     This module is not a source filter.
 
 
     This module is not a source filter.
 


@@ -50,19 +55,53 @@ METHODS
         indirect syntax met.
 
     *   If the key/value pair "hook => $hook" comes first, $hook will be
         indirect syntax met.
 
     *   If the key/value pair "hook => $hook" comes first, $hook will be

-        called for each error with the object name as $_[0], the method name
-        as $_[1], the current file as $_[2] and the line number as $_[3].
+        called for each error with a string representation of the object as
+        $_[0], the method name as $_[1], the current file as $_[2] and the
+        line number as $_[3]. If and only if the object is actually a block,
+        $_[0] is assured to start by '{'.

 
     *   Otherwise, a warning will be emitted for each indirect construct.
 
   "import"
     Magically called at each "use indirect". Turns the module off.
 
 
     *   Otherwise, a warning will be emitted for each indirect construct.
 
   "import"
     Magically called at each "use indirect". Turns the module off.
 

+FUNCTIONS
+  "msg $object, $method, $file, $line"
+    Returns the default error message generated by "indirect" when an
+    invalid construct is reported.
+

 CONSTANTS
   "I_THREADSAFE"
     True iff the module could have been built with thread-safety features
     enabled.
 
 CONSTANTS
   "I_THREADSAFE"
     True iff the module could have been built with thread-safety features
     enabled.
 

+  "I_FORKSAFE"
+    True iff this module could have been built with fork-safety features
+    enabled. This will always be true except on Windows where it's false for
+    perl 5.10.0 and below .
+
+DIAGNOSTICS
+  "Indirect call of method "%s" on object "%s" at %s line %d."
+    The default warning/exception message thrown when an indirect call on an
+    object is found.
+
+  "Indirect call of method "%s" on a block at %s line %d."
+    The default warning/exception message thrown when an indirect call on a
+    block is found.
+
+ENVIRONMENT
+  "PERL_INDIRECT_PM_DISABLE"
+    If this environment variable is set to true when the pragma is used for
+    the first time, the XS code won't be loaded and, although the 'indirect'
+    lexical hint will be set to true in the scope of use, the pragma itself
+    won't do anything. In this case, the pragma will always be considered to
+    be thread-safe, and as such "I_THREADSAFE" will be true. This is useful
+    for disabling "indirect" in production environments.
+
+    Note that clearing this variable after "indirect" was loaded has no
+    effect. If you want to reenable the pragma later, you also need to
+    reload it by deleting the 'indirect.pm' entry from %INC.
+

 CAVEATS
     The implementation was tweaked to work around several limitations of
     vanilla "perl" pragmas : it's thread safe, and doesn't suffer from a
 CAVEATS
     The implementation was tweaked to work around several limitations of
     vanilla "perl" pragmas : it's thread safe, and doesn't suffer from a


@@ -77,8 +116,11 @@ CAVEATS
     is due to a shortcoming in the way perl handles the hints hash, which is
     addressed in perl 5.10.
 
     is due to a shortcoming in the way perl handles the hints hash, which is
     addressed in perl 5.10.
 

+    The search for indirect method calls happens before constant folding.
+    Hence "my $x = new Class if 0" will be caught.
+

 DEPENDENCIES
 DEPENDENCIES

-    perl 5.8.
+    perl 5.8.1.

 
     XSLoader (standard since perl 5.006).
 
 
     XSLoader (standard since perl 5.006).
 


@@ -105,8 +147,11 @@ SUPPORT
 ACKNOWLEDGEMENTS
     Bram, for motivation and advices.
 
 ACKNOWLEDGEMENTS
     Bram, for motivation and advices.
 

+    Andrew Main and Florian Ragwitz, for testing on real-life code and
+    reporting issues.
+

 COPYRIGHT & LICENSE
 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.
 
     This program is free software; you can redistribute it and/or modify it
     under the same terms as Perl itself.