1 # Term::ANSIColor -- Color screen output using ANSI escape sequences.
3 # Copyright 1996, 1997, 1998, 2000, 2001, 2002, 2005, 2006, 2008, 2009
4 # Russ Allbery <rra@stanford.edu> and Zenin
5 # PUSH/POP support submitted 2007 by openmethods.com voice solutions
7 # This program is free software; you may redistribute it and/or modify it
8 # under the same terms as Perl itself.
10 # Ah, September, when the sysadmins turn colors and fall off the trees....
13 ##############################################################################
14 # Modules and declarations
15 ##############################################################################
17 package Term::ANSIColor;
23 use vars qw($AUTOLOAD $AUTOLOCAL $AUTORESET @COLORLIST @COLORSTACK $EACHLINE
24 @ISA @EXPORT @EXPORT_OK %EXPORT_TAGS $VERSION %ATTRIBUTES
29 @COLORLIST = qw(CLEAR RESET BOLD DARK UNDERLINE UNDERSCORE BLINK REVERSE
30 CONCEALED BLACK RED GREEN YELLOW BLUE MAGENTA CYAN WHITE
31 ON_BLACK ON_RED ON_GREEN ON_YELLOW ON_BLUE ON_MAGENTA
34 @EXPORT = qw(color colored);
35 @EXPORT_OK = qw(uncolor);
36 %EXPORT_TAGS = (constants => \@COLORLIST,
37 pushpop => [ @COLORLIST,
38 qw(PUSHCOLOR POPCOLOR LOCALCOLOR) ]);
39 Exporter::export_ok_tags ('pushpop');
42 ##############################################################################
43 # Internal data structures
44 ##############################################################################
46 %ATTRIBUTES = ('clear' => 0,
57 'black' => 30, 'on_black' => 40,
58 'red' => 31, 'on_red' => 41,
59 'green' => 32, 'on_green' => 42,
60 'yellow' => 33, 'on_yellow' => 43,
61 'blue' => 34, 'on_blue' => 44,
62 'magenta' => 35, 'on_magenta' => 45,
63 'cyan' => 36, 'on_cyan' => 46,
64 'white' => 37, 'on_white' => 47);
66 # Reverse lookup. Alphabetically first name for a sequence is preferred.
67 for (reverse sort keys %ATTRIBUTES) {
68 $ATTRIBUTES_R{$ATTRIBUTES{$_}} = $_;
71 ##############################################################################
72 # Implementation (constant form)
73 ##############################################################################
75 # Time to have fun! We now want to define the constant subs, which are named
76 # the same as the attributes above but in all caps. Each constant sub needs
77 # to act differently depending on whether $AUTORESET is set. Without
80 # BLUE "text\n" ==> "\e[34mtext\n"
82 # If $AUTORESET is set, we should instead get:
84 # BLUE "text\n" ==> "\e[34mtext\n\e[0m"
86 # The sub also needs to handle the case where it has no arguments correctly.
87 # Maintaining all of this as separate subs would be a major nightmare, as well
88 # as duplicate the %ATTRIBUTES hash, so instead we define an AUTOLOAD sub to
89 # define the constant subs on demand. To do that, we check the name of the
90 # called sub against the list of attributes, and if it's an all-caps version
91 # of one of them, we define the sub on the fly and then run it.
93 # If the environment variable ANSI_COLORS_DISABLED is set, just return the
94 # arguments without adding any escape sequences. This is to make it easier to
95 # write scripts that also work on systems without any ANSI support, like
98 if (defined $ENV{ANSI_COLORS_DISABLED}) {
102 ($sub = $AUTOLOAD) =~ s/^.*:://;
103 my $attr = $ATTRIBUTES{lc $sub};
104 if ($sub =~ /^[A-Z_]+$/ && defined $attr) {
105 $attr = "\e[" . $attr . 'm';
108 if (\$AUTORESET && \@_) {
109 return '$attr' . join ('', \@_) . "\e[0m";
110 } elsif (\$AUTOLOCAL && \@_) {
111 return PUSHCOLOR ('$attr') . join ('', \@_) . POPCOLOR;
113 return '$attr' . join ('', \@_);
120 Carp::croak ("undefined subroutine &$AUTOLOAD called");
124 # Append a new color to the top of the color stack and return the top of
128 my ($color) = ($text =~ m/^((?:\e\[[\d;]+m)+)/);
130 $color = $COLORSTACK[-1] . $color;
132 push (@COLORSTACK, $color);
136 # Pop the color stack and return the new top of the stack (or reset, if
137 # the stack is empty).
141 return $COLORSTACK[-1] . join ('', @_);
147 # Surround arguments with a push and a pop.
149 return PUSHCOLOR (join ('', @_)) . POPCOLOR ();
152 ##############################################################################
153 # Implementation (attribute string form)
154 ##############################################################################
156 # Return the escape code for a given set of color attributes.
158 return '' if defined $ENV{ANSI_COLORS_DISABLED};
159 my @codes = map { split } @_;
163 unless (defined $ATTRIBUTES{$_}) {
165 Carp::croak ("Invalid attribute name $_");
167 $attribute .= $ATTRIBUTES{$_} . ';';
170 return ($attribute ne '') ? "\e[${attribute}m" : undef;
173 # Return a list of named color attributes for a given set of escape codes.
174 # Escape sequences can be given with or without enclosing "\e[" and "m". The
175 # empty escape sequence '' or "\e[m" gives an empty list of attrs.
180 $escape =~ s/^\e\[//;
182 unless ($escape =~ /^((?:\d+;)*\d*)$/) {
184 Carp::croak ("Bad escape sequence $_");
186 push (@nums, split (/;/, $1));
189 $_ += 0; # Strip leading zeroes
190 my $name = $ATTRIBUTES_R{$_};
191 if (!defined $name) {
193 Carp::croak ("No name for escape sequence $_" );
195 push (@result, $name);
200 # Given a string and a set of attributes, returns the string surrounded by
201 # escape codes to set those attributes and then clear them at the end of the
202 # string. The attributes can be given either as an array ref as the first
203 # argument or as a list as the second and subsequent arguments. If $EACHLINE
204 # is set, insert a reset before each occurrence of the string $EACHLINE and
205 # the starting attribute code after the string $EACHLINE, so that no attribute
206 # crosses line delimiters (this is often desirable if the output is to be
207 # piped to a pager or some other program).
209 my ($string, @codes);
212 $string = join ('', @_);
217 return $string if defined $ENV{ANSI_COLORS_DISABLED};
218 if (defined $EACHLINE) {
219 my $attr = color (@codes);
221 map { ($_ ne $EACHLINE) ? $attr . $_ . "\e[0m" : $_ }
222 grep { length ($_) > 0 }
223 split (/(\Q$EACHLINE\E)/, $string);
225 return color (@codes) . $string . "\e[0m";
229 ##############################################################################
230 # Module return value and documentation
231 ##############################################################################
233 # Ensure we evaluate to true.
239 Term::ANSIColor - Color screen output using ANSI escape sequences
242 cyan colorize namespace runtime TMTOWTDI cmd.exe 4nt.exe command.com NT
243 ESC Delvare SSH OpenSSH aixterm ECMA-048 Fraktur overlining Zenin
244 reimplemented Allbery PUSHCOLOR POPCOLOR LOCALCOLOR openmethods.com
249 print color 'bold blue';
250 print "This text is bold blue.\n";
252 print "This text is normal.\n";
253 print colored ("Yellow on magenta.", 'yellow on_magenta'), "\n";
254 print "This text is normal.\n";
255 print colored ['yellow on_magenta'], 'Yellow on magenta.';
258 use Term::ANSIColor qw(uncolor);
259 print uncolor '01;31', "\n";
261 use Term::ANSIColor qw(:constants);
262 print BOLD, BLUE, "This text is in bold blue.\n", RESET;
264 use Term::ANSIColor qw(:constants);
266 local $Term::ANSIColor::AUTORESET = 1;
267 print BOLD BLUE "This text is in bold blue.\n";
268 print "This text is normal.\n";
271 use Term::ANSIColor qw(:pushpop);
272 print PUSHCOLOR RED ON_GREEN "This text is red on green.\n";
273 print PUSHCOLOR BLUE "This text is blue on green.\n";
274 print RESET BLUE "This text is just blue.\n";
275 print POPCOLOR "Back to red on green.\n";
276 print LOCALCOLOR GREEN ON_BLUE "This text is green on blue.\n";
277 print "This text is red on green.\n";
279 local $Term::ANSIColor::AUTOLOCAL = 1;
280 print ON_BLUE "This text is red on blue.\n";
281 print "This text is red on green.\n";
283 print POPCOLOR "Back to whatever we started as.\n";
287 This module has two interfaces, one through color() and colored() and the
288 other through constants. It also offers the utility function uncolor(),
289 which has to be explicitly imported to be used (see L</SYNOPSIS>).
291 color() takes any number of strings as arguments and considers them to be
292 space-separated lists of attributes. It then forms and returns the escape
293 sequence to set those attributes. It doesn't print it out, just returns
294 it, so you'll have to print it yourself if you want to (this is so that
295 you can save it as a string, pass it to something else, send it to a file
296 handle, or do anything else with it that you might care to).
298 uncolor() performs the opposite translation, turning escape sequences
299 into a list of strings.
301 The recognized non-color attributes are clear, reset, bold, dark, faint,
302 underline, underscore, blink, reverse, and concealed. Clear and reset
303 (reset to default attributes), dark and faint (dim and saturated), and
304 underline and underscore are equivalent, so use whichever is the most
305 intuitive to you. The recognized foreground color attributes are black,
306 red, green, yellow, blue, magenta, cyan, and white. The recognized
307 background color attributes are on_black, on_red, on_green, on_yellow,
308 on_blue, on_magenta, on_cyan, and on_white. Case is not significant.
310 Note that not all attributes are supported by all terminal types, and some
311 terminals may not support any of these sequences. Dark and faint, blink,
312 and concealed in particular are frequently not implemented.
314 Attributes, once set, last until they are unset (by sending the attribute
315 C<clear> or C<reset>). Be careful to do this, or otherwise your attribute
316 will last after your script is done running, and people get very annoyed
317 at having their prompt and typing changed to weird colors.
319 As an aid to help with this, colored() takes a scalar as the first
320 argument and any number of attribute strings as the second argument and
321 returns the scalar wrapped in escape codes so that the attributes will be
322 set as requested before the string and reset to normal after the string.
323 Alternately, you can pass a reference to an array as the first argument,
324 and then the contents of that array will be taken as attributes and color
325 codes and the remainder of the arguments as text to colorize.
327 Normally, colored() just puts attribute codes at the beginning and end of
328 the string, but if you set $Term::ANSIColor::EACHLINE to some string, that
329 string will be considered the line delimiter and the attribute will be set
330 at the beginning of each line of the passed string and reset at the end of
331 each line. This is often desirable if the output contains newlines and
332 you're using background colors, since a background color that persists
333 across a newline is often interpreted by the terminal as providing the
334 default background color for the next line. Programs like pagers can also
335 be confused by attributes that span lines. Normally you'll want to set
336 $Term::ANSIColor::EACHLINE to C<"\n"> to use this feature.
338 Alternately, if you import C<:constants>, you can use the constants CLEAR,
339 RESET, BOLD, DARK, UNDERLINE, UNDERSCORE, BLINK, REVERSE, CONCEALED,
340 BLACK, RED, GREEN, YELLOW, BLUE, MAGENTA, CYAN, WHITE, ON_BLACK, ON_RED,
341 ON_GREEN, ON_YELLOW, ON_BLUE, ON_MAGENTA, ON_CYAN, and ON_WHITE directly.
342 These are the same as color('attribute') and can be used if you prefer
345 print BOLD BLUE ON_WHITE "Text", RESET, "\n";
349 print colored ("Text", 'bold blue on_white'), "\n";
351 (Note that the newline is kept separate to avoid confusing the terminal as
352 described above since a background color is being used.)
354 When using the constants, if you don't want to have to remember to add the
355 C<, RESET> at the end of each print line, you can set
356 $Term::ANSIColor::AUTORESET to a true value. Then, the display mode will
357 automatically be reset if there is no comma after the constant. In other
358 words, with that variable set:
360 print BOLD BLUE "Text\n";
362 will reset the display mode afterward, whereas:
364 print BOLD, BLUE, "Text\n";
366 will not. If you are using background colors, you will probably want to
367 print the newline with a separate print statement to avoid confusing the
370 The subroutine interface has the advantage over the constants interface in
371 that only two subroutines are exported into your namespace, versus
372 twenty-two in the constants interface. On the flip side, the constants
373 interface has the advantage of better compile time error checking, since
374 misspelled names of colors or attributes in calls to color() and colored()
375 won't be caught until runtime whereas misspelled names of constants will
376 be caught at compile time. So, pollute your namespace with almost two
377 dozen subroutines that you may not even use that often, or risk a silly
378 bug by mistyping an attribute. Your choice, TMTOWTDI after all.
380 As of Term::ANSIColor 2.0, you can import C<:pushpop> and maintain a stack
381 of colors using PUSHCOLOR, POPCOLOR, and LOCALCOLOR. PUSHCOLOR takes the
382 attribute string that starts its argument and pushes it onto a stack of
383 attributes. POPCOLOR removes the top of the stack and restores the
384 previous attributes set by the argument of a prior PUSHCOLOR. LOCALCOLOR
385 surrounds its argument in a PUSHCOLOR and POPCOLOR so that the color
388 When using PUSHCOLOR, POPCOLOR, and LOCALCOLOR, it's particularly
389 important to not put commas between the constants.
391 print PUSHCOLOR BLUE "Text\n";
393 will correctly push BLUE onto the top of the stack.
395 print PUSHCOLOR, BLUE, "Text\n"; # wrong!
397 will not, and a subsequent pop won't restore the correct attributes.
398 PUSHCOLOR pushes the attributes set by its argument, which is normally a
399 string of color constants. It can't ask the terminal what the current
406 =item Bad escape sequence %s
408 (F) You passed an invalid ANSI escape sequence to uncolor().
410 =item Bareword "%s" not allowed while "strict subs" in use
412 (F) You probably mistyped a constant color name such as:
414 $Foobar = FOOBAR . "This line should be blue\n";
418 @Foobar = FOOBAR, "This line should be blue\n";
420 This will only show up under use strict (another good reason to run under
423 =item Invalid attribute name %s
425 (F) You passed an invalid attribute name to either color() or colored().
427 =item Name "%s" used only once: possible typo
429 (W) You probably mistyped a constant color name such as:
431 print FOOBAR "This text is color FOOBAR\n";
433 It's probably better to always use commas after constant names in order to
434 force the next error.
436 =item No comma allowed after filehandle
438 (F) You probably mistyped a constant color name such as:
440 print FOOBAR, "This text is color FOOBAR\n";
442 Generating this fatal compile error is one of the main advantages of using
443 the constants interface, since you'll immediately know if you mistype a
446 =item No name for escape sequence %s
448 (F) The ANSI escape sequence passed to uncolor() contains escapes which
449 aren't recognized and can't be translated to names.
457 =item ANSI_COLORS_DISABLED
459 If this environment variable is set, all of the functions defined by this
460 module (color(), colored(), and all of the constants not previously used
461 in the program) will not output any escape sequences and instead will just
462 return the empty string or pass through the original text as appropriate.
463 This is intended to support easy use of scripts using this module on
464 platforms that don't support ANSI escape sequences.
466 For it to have its proper effect, this environment variable must be set
467 before any color constants are used in the program.
473 It would be nice if one could leave off the commas around the constants
474 entirely and just say:
476 print BOLD BLUE ON_WHITE "Text\n" RESET;
478 but the syntax of Perl doesn't allow this. You need a comma after the
479 string. (Of course, you may consider it a bug that commas between all the
480 constants aren't required, in which case you may feel free to insert
481 commas unless you're using $Term::ANSIColor::AUTORESET or
484 For easier debugging, you may prefer to always use the commas when not
485 setting $Term::ANSIColor::AUTORESET or PUSHCOLOR/POPCOLOR so that you'll
486 get a fatal compile error rather than a warning.
490 The codes generated by this module are standard terminal control codes,
491 complying with ECMA-048 and ISO 6429 (generally referred to as "ANSI
492 color" for the color codes). The non-color control codes (bold, dark,
493 italic, underline, and reverse) are part of the earlier ANSI X3.64
494 standard for control sequences for video terminals and peripherals.
496 Note that not all displays are ISO 6429-compliant, or even X3.64-compliant
497 (or are even attempting to be so). This module will not work as expected
498 on displays that do not honor these escape sequences, such as cmd.exe,
499 4nt.exe, and command.com under either Windows NT or Windows 2000. They
500 may just be ignored, or they may display as an ESC character followed by
501 some apparent garbage.
503 Jean Delvare provided the following table of different common terminal
504 emulators and their support for the various attributes and others have
505 helped me flesh it out:
507 clear bold faint under blink reverse conceal
508 ------------------------------------------------------------------------
509 xterm yes yes no yes bold yes yes
510 linux yes yes yes bold yes yes no
511 rxvt yes yes no yes bold/black yes no
512 dtterm yes yes yes yes reverse yes yes
513 teraterm yes reverse no yes rev/red yes no
514 aixterm kinda normal no yes no yes yes
515 PuTTY yes color no yes no yes no
516 Windows yes no no no no yes no
517 Cygwin SSH yes yes no color color color yes
518 Mac Terminal yes yes no yes yes yes yes
520 Windows is Windows telnet, Cygwin SSH is the OpenSSH implementation under
521 Cygwin on Windows NT, and Mac Terminal is the Terminal application in Mac
522 OS X. Where the entry is other than yes or no, that emulator displays the
523 given attribute as something else instead. Note that on an aixterm, clear
524 doesn't reset colors; you have to explicitly set the colors back to what
525 you want. More entries in this table are welcome.
527 Note that codes 3 (italic), 6 (rapid blink), and 9 (strike-through) are
528 specified in ANSI X3.64 and ECMA-048 but are not commonly supported by
529 most displays and emulators and therefore aren't supported by this module
530 at the present time. ECMA-048 also specifies a large number of other
531 attributes, including a sequence of attributes for font changes, Fraktur
532 characters, double-underlining, framing, circling, and overlining. As
533 none of these attributes are widely supported or useful, they also aren't
534 currently supported by this module.
538 ECMA-048 is available on-line (at least at the time of this writing) at
539 L<http://www.ecma-international.org/publications/standards/ECMA-048.HTM>.
541 ISO 6429 is available from ISO for a charge; the author of this module
542 does not own a copy of it. Since the source material for ISO 6429 was
543 ECMA-048 and the latter is available for free, there seems little reason
544 to obtain the ISO standard.
546 The current version of this module is always available from its web site
547 at L<http://www.eyrie.org/~eagle/software/ansicolor/>. It is also part of
548 the Perl core distribution as of 5.6.0.
552 Original idea (using constants) by Zenin, reimplemented using subs by Russ
553 Allbery <rra@stanford.edu>, and then combined with the original idea by
554 Russ with input from Zenin. Russ Allbery now maintains this module.
556 =head1 COPYRIGHT AND LICENSE
558 Copyright 1996, 1997, 1998, 2000, 2001, 2002, 2005, 2006, 2008, 2009 Russ
559 Allbery <rra@stanford.edu> and Zenin. This program is free software; you
560 may redistribute it and/or modify it under the same terms as Perl itself.
562 PUSHCOLOR, POPCOLOR, and LOCALCOLOR were contributed by openmethods.com