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   1  package English;
   2  
   3  our $VERSION = '1.04';
   4  
   5  require Exporter;
   6  @ISA = qw(Exporter);
   7  
   8  =head1 NAME
   9  
  10  English - use nice English (or awk) names for ugly punctuation variables
  11  
  12  =head1 SYNOPSIS
  13  
  14      use English qw( -no_match_vars ) ;  # Avoids regex performance penalty
  15      use English;
  16      ...
  17      if ($ERRNO =~ /denied/) { ... }
  18  
  19  =head1 DESCRIPTION
  20  
  21  This module provides aliases for the built-in variables whose
  22  names no one seems to like to read.  Variables with side-effects
  23  which get triggered just by accessing them (like $0) will still 
  24  be affected.
  25  
  26  For those variables that have an B<awk> version, both long
  27  and short English alternatives are provided.  For example, 
  28  the C<$/> variable can be referred to either $RS or 
  29  $INPUT_RECORD_SEPARATOR if you are using the English module.
  30  
  31  See L<perlvar> for a complete list of these.
  32  
  33  =head1 PERFORMANCE
  34  
  35  This module can provoke sizeable inefficiencies for regular expressions,
  36  due to unfortunate implementation details.  If performance matters in
  37  your application and you don't need $PREMATCH, $MATCH, or $POSTMATCH,
  38  try doing
  39  
  40     use English qw( -no_match_vars ) ;
  41  
  42  .  B<It is especially important to do this in modules to avoid penalizing
  43  all applications which use them.>
  44  
  45  =cut
  46  
  47  no warnings;
  48  
  49  my $globbed_match ;
  50  
  51  # Grandfather $NAME import
  52  sub import {
  53      my $this = shift;
  54      my @list = grep { ! /^-no_match_vars$/ } @_ ;
  55      local $Exporter::ExportLevel = 1;
  56      if ( @_ == @list ) {
  57          *EXPORT = \@COMPLETE_EXPORT ;
  58          $globbed_match ||= (
  59          eval q{
  60          *MATCH                = *&    ;
  61          *PREMATCH            = *`    ;
  62          *POSTMATCH            = *'    ;
  63          1 ;
  64             }
  65          || do {
  66          require Carp ;
  67          Carp::croak("Can't create English for match leftovers: $@") ;
  68          }
  69      ) ;
  70      }
  71      else {
  72          *EXPORT = \@MINIMAL_EXPORT ;
  73      }
  74      Exporter::import($this,grep {s/^\$/*/} @list);
  75  }
  76  
  77  @MINIMAL_EXPORT = qw(
  78      *ARG
  79      *LAST_PAREN_MATCH
  80      *INPUT_LINE_NUMBER
  81      *NR
  82      *INPUT_RECORD_SEPARATOR
  83      *RS
  84      *OUTPUT_AUTOFLUSH
  85      *OUTPUT_FIELD_SEPARATOR
  86      *OFS
  87      *OUTPUT_RECORD_SEPARATOR
  88      *ORS
  89      *LIST_SEPARATOR
  90      *SUBSCRIPT_SEPARATOR
  91      *SUBSEP
  92      *FORMAT_PAGE_NUMBER
  93      *FORMAT_LINES_PER_PAGE
  94      *FORMAT_LINES_LEFT
  95      *FORMAT_NAME
  96      *FORMAT_TOP_NAME
  97      *FORMAT_LINE_BREAK_CHARACTERS
  98      *FORMAT_FORMFEED
  99      *CHILD_ERROR
 100      *OS_ERROR
 101      *ERRNO
 102      *EXTENDED_OS_ERROR
 103      *EVAL_ERROR
 104      *PROCESS_ID
 105      *PID
 106      *REAL_USER_ID
 107      *UID
 108      *EFFECTIVE_USER_ID
 109      *EUID
 110      *REAL_GROUP_ID
 111      *GID
 112      *EFFECTIVE_GROUP_ID
 113      *EGID
 114      *PROGRAM_NAME
 115      *PERL_VERSION
 116      *ACCUMULATOR
 117      *COMPILING
 118      *DEBUGGING
 119      *SYSTEM_FD_MAX
 120      *INPLACE_EDIT
 121      *PERLDB
 122      *BASETIME
 123      *WARNING
 124      *EXECUTABLE_NAME
 125      *OSNAME
 126      *LAST_REGEXP_CODE_RESULT
 127      *EXCEPTIONS_BEING_CAUGHT
 128      *LAST_SUBMATCH_RESULT
 129      @LAST_MATCH_START
 130      @LAST_MATCH_END
 131  );
 132  
 133  
 134  @MATCH_EXPORT = qw(
 135      *MATCH
 136      *PREMATCH
 137      *POSTMATCH
 138  );
 139  
 140  @COMPLETE_EXPORT = ( @MINIMAL_EXPORT, @MATCH_EXPORT ) ;
 141  
 142  # The ground of all being. @ARG is deprecated (5.005 makes @_ lexical)
 143  
 144      *ARG                    = *_    ;
 145  
 146  # Matching.
 147  
 148      *LAST_PAREN_MATCH            = *+    ;
 149      *LAST_SUBMATCH_RESULT            = *^N ;
 150      *LAST_MATCH_START            = *-{ARRAY} ;
 151      *LAST_MATCH_END                = *+{ARRAY} ;
 152  
 153  # Input.
 154  
 155      *INPUT_LINE_NUMBER            = *.    ;
 156          *NR                    = *.    ;
 157      *INPUT_RECORD_SEPARATOR            = */    ;
 158          *RS                    = */    ;
 159  
 160  # Output.
 161  
 162      *OUTPUT_AUTOFLUSH            = *|    ;
 163      *OUTPUT_FIELD_SEPARATOR            = *,    ;
 164          *OFS                = *,    ;
 165      *OUTPUT_RECORD_SEPARATOR        = *\    ;
 166          *ORS                = *\    ;
 167  
 168  # Interpolation "constants".
 169  
 170      *LIST_SEPARATOR                = *"    ;
 171      *SUBSCRIPT_SEPARATOR            = *;    ;
 172          *SUBSEP                = *;    ;
 173  
 174  # Formats
 175  
 176      *FORMAT_PAGE_NUMBER            = *%    ;
 177      *FORMAT_LINES_PER_PAGE            = *=    ;
 178      *FORMAT_LINES_LEFT            = *-    ;
 179      *FORMAT_NAME                = *~    ;
 180      *FORMAT_TOP_NAME            = *^    ;
 181      *FORMAT_LINE_BREAK_CHARACTERS        = *:    ;
 182      *FORMAT_FORMFEED            = *^L    ;
 183  
 184  # Error status.
 185  
 186      *CHILD_ERROR                = *?    ;
 187      *OS_ERROR                = *!    ;
 188          *ERRNO                = *!    ;
 189      *OS_ERROR                = *!    ;
 190          *ERRNO                = *!    ;
 191      *EXTENDED_OS_ERROR            = *^E    ;
 192      *EVAL_ERROR                = *@    ;
 193  
 194  # Process info.
 195  
 196      *PROCESS_ID                = *$    ;
 197          *PID                = *$    ;
 198      *REAL_USER_ID                = *<    ;
 199          *UID                = *<    ;
 200      *EFFECTIVE_USER_ID            = *>    ;
 201          *EUID                = *>    ;
 202      *REAL_GROUP_ID                = *(    ;
 203          *GID                = *(    ;
 204      *EFFECTIVE_GROUP_ID            = *)    ;
 205          *EGID                = *)    ;
 206      *PROGRAM_NAME                = *0    ;
 207  
 208  # Internals.
 209  
 210      *PERL_VERSION                = *^V    ;
 211      *ACCUMULATOR                = *^A    ;
 212      *COMPILING                = *^C    ;
 213      *DEBUGGING                = *^D    ;
 214      *SYSTEM_FD_MAX                = *^F    ;
 215      *INPLACE_EDIT                = *^I    ;
 216      *PERLDB                    = *^P    ;
 217      *LAST_REGEXP_CODE_RESULT        = *^R    ;
 218      *EXCEPTIONS_BEING_CAUGHT        = *^S    ;
 219      *BASETIME                = *^T    ;
 220      *WARNING                = *^W    ;
 221      *EXECUTABLE_NAME            = *^X    ;
 222      *OSNAME                    = *^O    ;
 223  
 224  # Deprecated.
 225  
 226  #    *ARRAY_BASE                = *[    ;
 227  #    *OFMT                    = *#    ;
 228  #    *OLD_PERL_VERSION            = *]    ;
 229  
 230  1;