X-Git-Url: http://git.vpit.fr/?p=perl%2Fmodules%2Findirect.git;a=blobdiff_plain;f=lib%2Findirect.pm;h=9511a53c20c8743a14458cfb3d6c5c1e99ec796d;hp=ff3d34e02b2e8ad8f608f9b22d715a3dcfcad414;hb=dffe18044b67f8d86bf82121ea97c2c28f3335d0;hpb=c88f53009246bbc1af1789f746acc5d841fc0ae8 diff --git a/lib/indirect.pm b/lib/indirect.pm index ff3d34e..9511a53 100644 --- a/lib/indirect.pm +++ b/lib/indirect.pm @@ -7,55 +7,58 @@ use warnings; =head1 NAME -indirect - Lexically warn about using the indirect object syntax. +indirect - Lexically warn about using the indirect method call syntax. =head1 VERSION -Version 0.25 +Version 0.26 =cut our $VERSION; BEGIN { - $VERSION = '0.25'; + $VERSION = '0.26'; } =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), 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 is not defined, C actually compiles to C<< $x->swoosh >>). -In L, 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 has not been declared in the current package, C actually compiles to C<< $x->foo >>, and C<< foo { key => 1 } >> to C<< 'key'->foo(1) >>. +In L, 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, C, C or C). +This pragma currently does not warn for core functions (C, C, C or C). This may change in the future, or may be added as optional features that would be enabled by passing options to C. This module is B a source filter. @@ -75,7 +78,14 @@ BEGIN { =head1 METHODS -=head2 C<< unimport [ 'global', hook => $hook | 'fatal' ] >> +=head2 C + + no indirect; + no indirect 'fatal'; + no indirect hook => sub { my ($obj, $name, $file, $line) = @_; ... }; + no indirect 'global'; + no indirect 'global, 'fatal'; + no indirect 'global', hook => sub { ... }; Magically called when C is encountered. Turns the module on. @@ -85,16 +95,20 @@ The policy to apply depends on what is first found in C<@opts> : =item * -If it is a string that matches C, the compilation will croak on the first indirect syntax met. +If it is a string that matches C, the compilation will croak when the first indirect method call is found. + +This option is mutually exclusive with the C<'hook'> option. =item * If the key/value pair C<< hook => $hook >> comes first, C<$hook> will be called for each error with a string representation of the object as C<$_[0]>, the method name as C<$_[1]>, the current file as C<$_[2]> and the line number as C<$_[3]>. If and only if the object is actually a block, C<$_[0]> is assured to start by C<'{'>. +This option is mutually exclusive with the C<'fatal'> option. + =item * -If none of C and C are specified, a warning will be emitted for each indirect construct. +If none of C and C are specified, a warning will be emitted for each indirect method call. =item * @@ -121,24 +135,32 @@ Note that if another policy is installed by a C statement further i =cut +sub _no_hook_and_fatal { + require Carp; + Carp::croak("The 'fatal' and 'hook' options are mutually exclusive"); +} + sub unimport { shift; - my $hook; - my $global; + my ($global, $fatal, $hook); + while (@_) { my $arg = shift; if ($arg eq 'hook') { - last if $hook; + _no_hook_and_fatal() if $fatal; $hook = shift; } elsif ($arg =~ /^:?fatal$/i) { - last if $hook; - $hook = sub { die msg(@_) }; + _no_hook_and_fatal() if defined $hook; + $fatal = 1; } elsif ($arg =~ /^:?global$/i) { $global = 1; } } - $hook = sub { warn msg(@_) } unless defined $hook; + + unless (defined $hook) { + $hook = $fatal ? sub { die msg(@_) } : sub { warn msg(@_) }; + } $^H |= 0x00020000; if ($global) { @@ -153,6 +175,8 @@ sub unimport { =head2 C + use indirect; + Magically called at each C. Turns the module off. As explained in L's description, an C statement will lexically override a global policy previously installed by C (if there's one). @@ -168,9 +192,11 @@ sub import { =head1 FUNCTIONS -=head2 C +=head2 C + + my $msg = msg($object, $method, $file, $line); -Returns the default error message generated by C when an invalid construct is reported. +Returns the default error message that C generates when an indirect method call is reported. =cut @@ -197,11 +223,11 @@ This will always be true except on Windows where it's false for perl 5.10.0 and =head2 C -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 -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 @@ -218,7 +244,7 @@ If you want to re-enable the pragma later, you also need to reload it by deletin The implementation was tweaked to work around several limitations of vanilla C pragmas : it's thread safe, and does not suffer from a C bug that causes all pragmas to propagate into Cd scopes. -Before C 5.12, C (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 or C). +Before C 5.12, C (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 or C). If you use C 5.12 or greater, those constructs are correctly reported. With 5.8 perls, the pragma does not propagate into C. @@ -234,7 +260,7 @@ L 5.8.1. A C compiler. This module may happen to build with a C++ compiler as well, but don't rely on it, as no guarantee is made in this regard. -L (standard since perl 5.006). +L (standard since perl 5), L (since perl 5.006). =head1 AUTHOR