=head1 NAME
-indirect - Lexically warn about using the indirect object syntax.
+indirect - Lexically warn about using the indirect method call syntax.
=head1 VERSION
=head1 SYNOPSIS
- # In a script
- no indirect;
+In a script :
+
+ no indirect; # lexically enables the pragma
my $x = new Apple 1, 2, 3; # warns
{
- use indirect;
- my $y = new Pear; # ok
+ use indirect; # lexically disables the pragma
+ my $y = new Pear; # legit, does not warn
{
+ # lexically specify an hook called for each indirect construct
no indirect hook => sub {
die "You really wanted $_[0]\->$_[1] at $_[2]:$_[3]"
};
- # croaks 'You really wanted Pineapple->new at blurp.pm:13'
- my $z = new Pineapple 'fresh';
+ my $z = new Pineapple 'fresh'; # croaks 'You really wanted...'
}
}
- try { ... }; # warns
+ try { ... }; # warns if try() hasn't been declared in this package
- no indirect ':fatal'; # or 'FATAL', or ':Fatal' ...
+ no indirect 'fatal'; # or ':fatal', 'FATAL', ':Fatal' ...
if (defied $foo) { ... } # croaks, note the typo
- # Globally enabled from the command-line
+Global uses :
+
+ # Globally enable the pragma from the command-line
perl -M-indirect=global -e 'my $x = new Banana;' # warns
- # Or globally enabled each time perl is executed
- export PERL5OPT="-M-indirect=global"
- perl -e 'my $y = new Coconut;' # warns
+ # Globally enforce the pragma each time perl is executed
+ export PERL5OPT="-M-indirect=global,fatal"
+ perl -e 'my $y = new Coconut;' # croaks
=head1 DESCRIPTION
-When enabled (or disabled as some may prefer to say, since you actually turn it on by calling C<no indirect>), this pragma warns about indirect object syntax constructs that may have slipped into your code.
+When enabled, this pragma warns about indirect method calls that are present in your code.
-This syntax is now considered harmful, since its parsing has many quirks and its use is error prone (when C<swoosh> is not defined, C<swoosh $x> actually compiles to C<< $x->swoosh >>).
-In L<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.
+The indirect syntax is now considered harmful, since its parsing has many quirks and its use is error prone : when the subroutine C<foo> has not been declared in the current package, C<foo $x> actually compiles to C<< $x->foo >>, and C<< foo { key => 1 } >> to C<< 'key'->foo(1) >>.
+In L<http://www.shadowcat.co.uk/blog/matt-s-trout/indirect-but-still-fatal>, Matt S. Trout gives an example of an undesirable indirect method call on a block that can cause a particularly bewildering error.
-It currently does not warn for core functions (C<print>, C<say>, C<exec> or C<system>).
+This pragma currently does not warn for core functions (C<print>, C<say>, C<exec> or C<system>).
This may change in the future, or may be added as optional features that would be enabled by passing options to C<unimport>.
This module is B<not> a source filter.
=item *
-If it is a string that matches C</^:?fatal$/i>, the compilation will croak on the first indirect syntax met.
+If it is a string that matches C</^:?fatal$/i>, the compilation will croak when the first indirect method call is found.
=item *
=item *
-If none of C<fatal> and C<hook> are specified, a warning will be emitted for each indirect construct.
+If none of C<fatal> and C<hook> are specified, a warning will be emitted for each indirect method call.
=item *
=head2 C<msg $object, $method, $file, $line>
-Returns the default error message generated by C<indirect> when an invalid construct is reported.
+Returns the default error message that C<indirect> generates when an indirect method call is reported.
=cut
=head2 C<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.
+The default warning/exception message thrown when an indirect method call on an object is found.
=head2 C<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.
+The default warning/exception message thrown when an indirect method call on a block is found.
=head1 ENVIRONMENT
The implementation was tweaked to work around several limitations of vanilla C<perl> pragmas : it's thread safe, and does not suffer from a C<perl 5.8.x-5.10.0> bug that causes all pragmas to propagate into C<require>d scopes.
-Before C<perl> 5.12, C<meth $obj> (no semicolon) at the end of a file is not seen as an indirect object syntax, although it is as soon as there is another token before the end (as in C<meth $obj;> or C<meth $obj 1>).
+Before C<perl> 5.12, C<meth $obj> (no semicolon) at the end of a file is not seen as an indirect method call, although it is as soon as there is another token before the end (as in C<meth $obj;> or C<meth $obj 1>).
If you use C<perl> 5.12 or greater, those constructs are correctly reported.
With 5.8 perls, the pragma does not propagate into C<eval STRING>.