indirect - Lexically warn about using the indirect object syntax.
VERSION
- Version 0.17
+ Version 0.21
SYNOPSIS
# In a script
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 for core functions ("print", "say", "exec" or
"system"). This may change in the future, or may be added as optional
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
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
Hence "my $x = new Class if 0" will be caught.
DEPENDENCIES
- perl 5.8.
+ perl 5.8.1.
XSLoader (standard since perl 5.006).
reporting issues.
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.