package English;
+our $VERSION = '1.03';
+
require Exporter;
@ISA = (Exporter);
=head1 SYNOPSIS
+ use English qw( -no_match_vars ) ; # Avoids regex performance penalty
use English;
...
if ($ERRNO =~ /denied/) { ... }
See L<perlvar> for a complete list of these.
+=head1 PERFORMANCE
+
+This module can provoke sizeable inefficiencies for regular expressions,
+due to unfortunate implementation details. If performance matters in
+your application and you don't need $PREMATCH, $MATCH, or $POSTMATCH,
+try doing
+
+ use English qw( -no_match_vars ) ;
+
+. B<It is especially important to do this in modules to avoid penalizing
+all applications which use them.>
+
=cut
-local $^W = 0;
+no warnings;
+
+my $globbed_match ;
# Grandfather $NAME import
sub import {
my $this = shift;
- my @list = @_;
+ my @list = grep { ! /^-no_match_vars$/ } @_ ;
local $Exporter::ExportLevel = 1;
+ if ( @_ == @list ) {
+ *EXPORT = \@COMPLETE_EXPORT ;
+ $globbed_match ||= (
+ eval q{
+ *MATCH = *& ;
+ *PREMATCH = *` ;
+ *POSTMATCH = *' ;
+ 1 ;
+ }
+ || do {
+ require Carp ;
+ Carp::croak("Can't create English for match leftovers: $@") ;
+ }
+ ) ;
+ }
+ else {
+ *EXPORT = \@MINIMAL_EXPORT ;
+ }
Exporter::import($this,grep {s/^\$/*/} @list);
}
-@EXPORT = qw(
+@MINIMAL_EXPORT = qw(
*ARG
- *MATCH
- *PREMATCH
- *POSTMATCH
*LAST_PAREN_MATCH
*INPUT_LINE_NUMBER
*NR
*PROGRAM_NAME
*PERL_VERSION
*ACCUMULATOR
+ *COMPILING
*DEBUGGING
*SYSTEM_FD_MAX
*INPLACE_EDIT
*WARNING
*EXECUTABLE_NAME
*OSNAME
+ *LAST_REGEXP_CODE_RESULT
+ *EXCEPTIONS_BEING_CAUGHT
+ *LAST_SUBMATCH_RESULT
+ @LAST_MATCH_START
+ @LAST_MATCH_END
);
+
+@MATCH_EXPORT = qw(
+ *MATCH
+ *PREMATCH
+ *POSTMATCH
+);
+
+@COMPLETE_EXPORT = ( @MINIMAL_EXPORT, @MATCH_EXPORT ) ;
+
# The ground of all being. @ARG is deprecated (5.005 makes @_ lexical)
*ARG = *_ ;
# Matching.
- *MATCH = *& ;
- *PREMATCH = *` ;
- *POSTMATCH = *' ;
*LAST_PAREN_MATCH = *+ ;
+ *LAST_SUBMATCH_RESULT = *^N ;
+ *LAST_MATCH_START = *-{ARRAY} ;
+ *LAST_MATCH_END = *+{ARRAY} ;
# Input.
*CHILD_ERROR = *? ;
*OS_ERROR = *! ;
*ERRNO = *! ;
+ *OS_ERROR = *! ;
+ *ERRNO = *! ;
*EXTENDED_OS_ERROR = *^E ;
*EVAL_ERROR = *@ ;
# Internals.
- *PERL_VERSION = *] ;
+ *PERL_VERSION = *^V ;
*ACCUMULATOR = *^A ;
+ *COMPILING = *^C ;
*DEBUGGING = *^D ;
*SYSTEM_FD_MAX = *^F ;
*INPLACE_EDIT = *^I ;
*PERLDB = *^P ;
+ *LAST_REGEXP_CODE_RESULT = *^R ;
+ *EXCEPTIONS_BEING_CAUGHT = *^S ;
*BASETIME = *^T ;
*WARNING = *^W ;
*EXECUTABLE_NAME = *^X ;
# *ARRAY_BASE = *[ ;
# *OFMT = *# ;
-# *MULTILINE_MATCHING = ** ;
+# *OLD_PERL_VERSION = *] ;
1;