Perl English -
use English; names for ugly punctuation variables

Provide aliases for the built-in variables whose names no one seems to like to read. Full description

Used by foreach, grep, map, print, unlink and various unary functions including ord, int.
pattern matching m//, s///, and tr/// when no =~ is used
string preceeding last match
string matched
string following last match
last bracket matched/
$n = 1 or 2 …
text last matched
Input            Output
$| =1;
defaultes to \n

avoids needing to add \n to prints
BUT printf still needs it!
Interpolation "constants"
Error status
use Errno;
if ($!{ENOENT}) { $OS_ERROR $!
 if (open(FH, $filename)) {
                        # Here $! is NOT meaningful.
        ...                    } 
        else {
                # ONLY here is $! meaningful.

Process info.
value of -i switch $BASETIME
when program began running (seconds since the epoch )
$^F (usually 2)

The ground of all being.
@ARG @_ are deprecated (5.005 makes @_ lexical)
$OFMT $#

Variables with side-effects which get triggered just by accessing them (like $0 == ProgramName) will still be affected.

See perlvar for a complete list of these.

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