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 FAINT UNDERLINE UNDERSCORE BLINK
30 REVERSE CONCEALED BLACK RED GREEN YELLOW BLUE MAGENTA
31 CYAN WHITE ON_BLACK ON_RED ON_GREEN ON_YELLOW ON_BLUE
32 ON_MAGENTA ON_CYAN ON_WHITE);
34 @EXPORT = qw(color colored);
35 @EXPORT_OK = qw(uncolor colorstrip colorvalid);
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 $ENV{ANSI_COLORS_DISABLED}) {
101 if ($AUTOLOAD =~ /^([\w:]*::([A-Z_]+))$/ and defined $ATTRIBUTES{lc $2}) {
103 my $attr = "\e[" . $ATTRIBUTES{lc $2} . 'm';
106 if (\$AUTORESET && \@_) {
107 return '$attr' . join ('', \@_) . "\e[0m";
108 } elsif (\$AUTOLOCAL && \@_) {
109 return PUSHCOLOR ('$attr') . join ('', \@_) . POPCOLOR;
111 return '$attr' . join ('', \@_);
118 Carp::croak ("undefined subroutine &$AUTOLOAD called");
122 # Append a new color to the top of the color stack and return the top of
126 my ($color) = ($text =~ m/^((?:\e\[[\d;]+m)+)/);
128 $color = $COLORSTACK[-1] . $color;
130 push (@COLORSTACK, $color);
134 # Pop the color stack and return the new top of the stack (or reset, if
135 # the stack is empty).
139 return $COLORSTACK[-1] . join ('', @_);
145 # Surround arguments with a push and a pop.
147 return PUSHCOLOR (join ('', @_)) . POPCOLOR ();
150 ##############################################################################
151 # Implementation (attribute string form)
152 ##############################################################################
154 # Return the escape code for a given set of color attributes.
156 return '' if defined $ENV{ANSI_COLORS_DISABLED};
157 my @codes = map { split } @_;
161 unless (defined $ATTRIBUTES{$_}) {
163 Carp::croak ("Invalid attribute name $_");
165 $attribute .= $ATTRIBUTES{$_} . ';';
168 return ($attribute ne '') ? "\e[${attribute}m" : undef;
171 # Return a list of named color attributes for a given set of escape codes.
172 # Escape sequences can be given with or without enclosing "\e[" and "m". The
173 # empty escape sequence '' or "\e[m" gives an empty list of attrs.
178 $escape =~ s/^\e\[//;
180 unless ($escape =~ /^((?:\d+;)*\d*)$/) {
182 Carp::croak ("Bad escape sequence $escape");
184 push (@nums, split (/;/, $1));
187 $_ += 0; # Strip leading zeroes
188 my $name = $ATTRIBUTES_R{$_};
189 if (!defined $name) {
191 Carp::croak ("No name for escape sequence $_" );
193 push (@result, $name);
198 # Given a string and a set of attributes, returns the string surrounded by
199 # escape codes to set those attributes and then clear them at the end of the
200 # string. The attributes can be given either as an array ref as the first
201 # argument or as a list as the second and subsequent arguments. If $EACHLINE
202 # is set, insert a reset before each occurrence of the string $EACHLINE and
203 # the starting attribute code after the string $EACHLINE, so that no attribute
204 # crosses line delimiters (this is often desirable if the output is to be
205 # piped to a pager or some other program).
207 my ($string, @codes);
210 $string = join ('', @_);
215 return $string if defined $ENV{ANSI_COLORS_DISABLED};
216 if (defined $EACHLINE) {
217 my $attr = color (@codes);
219 map { ($_ ne $EACHLINE) ? $attr . $_ . "\e[0m" : $_ }
220 grep { length ($_) > 0 }
221 split (/(\Q$EACHLINE\E)/, $string);
223 return color (@codes) . $string . "\e[0m";
227 # Given a string, strip the ANSI color codes out of that string and return the
228 # result. This removes only ANSI color codes, not movement codes and other
232 for my $string (@string) {
233 $string =~ s/\e\[[\d;]*m//g;
235 return wantarray ? @string : join ('', @string);
238 # Given a list of color attributes (arguments for color, for instance), return
239 # true if they're all valid or false if any of them are invalid.
241 my @codes = map { split } @_;
243 unless (defined $ATTRIBUTES{lc $_}) {
250 ##############################################################################
251 # Module return value and documentation
252 ##############################################################################
254 # Ensure we evaluate to true.
260 Term::ANSIColor - Color screen output using ANSI escape sequences
263 cyan colorize namespace runtime TMTOWTDI cmd.exe 4nt.exe command.com NT
264 ESC Delvare SSH OpenSSH aixterm ECMA-048 Fraktur overlining Zenin
265 reimplemented Allbery PUSHCOLOR POPCOLOR LOCALCOLOR openmethods.com
270 print color 'bold blue';
271 print "This text is bold blue.\n";
273 print "This text is normal.\n";
274 print colored ("Yellow on magenta.", 'yellow on_magenta'), "\n";
275 print "This text is normal.\n";
276 print colored ['yellow on_magenta'], 'Yellow on magenta.';
279 use Term::ANSIColor qw(uncolor);
280 print uncolor ('01;31'), "\n";
282 use Term::ANSIColor qw(colorstrip);
283 print colorstrip '\e[1mThis is bold\e[0m', "\n";
285 use Term::ANSIColor qw(colorvalid);
286 my $valid = colorvalid ('blue bold', 'on_magenta');
287 print "Color string is ", $valid ? "valid\n" : "invalid\n";
289 use Term::ANSIColor qw(:constants);
290 print BOLD, BLUE, "This text is in bold blue.\n", RESET;
292 use Term::ANSIColor qw(:constants);
294 local $Term::ANSIColor::AUTORESET = 1;
295 print BOLD BLUE "This text is in bold blue.\n";
296 print "This text is normal.\n";
299 use Term::ANSIColor qw(:pushpop);
300 print PUSHCOLOR RED ON_GREEN "This text is red on green.\n";
301 print PUSHCOLOR BLUE "This text is blue on green.\n";
302 print RESET BLUE "This text is just blue.\n";
303 print POPCOLOR "Back to red on green.\n";
304 print LOCALCOLOR GREEN ON_BLUE "This text is green on blue.\n";
305 print "This text is red on green.\n";
307 local $Term::ANSIColor::AUTOLOCAL = 1;
308 print ON_BLUE "This text is red on blue.\n";
309 print "This text is red on green.\n";
311 print POPCOLOR "Back to whatever we started as.\n";
315 This module has two interfaces, one through color() and colored() and the
316 other through constants. It also offers the utility functions uncolor(),
317 colorstrip(), and colorvalid(), which have to be explicitly imported to be
318 used (see L</SYNOPSIS>).
320 =head2 Function Interface
322 color() takes any number of strings as arguments and considers them to be
323 space-separated lists of attributes. It then forms and returns the escape
324 sequence to set those attributes. It doesn't print it out, just returns
325 it, so you'll have to print it yourself if you want to (this is so that
326 you can save it as a string, pass it to something else, send it to a file
327 handle, or do anything else with it that you might care to). color()
328 throws an exception if given an invalid attribute, so you can also use it
329 to check attribute names for validity (see L</EXAMPLES>).
331 uncolor() performs the opposite translation, turning escape sequences
332 into a list of strings.
334 colorstrip() removes all color escape sequences from the provided strings,
335 returning the modified strings separately in array context or joined
336 together in scalar context. Its arguments are not modified.
338 colorvalid() takes attribute strings the same as color() and returns true
339 if all attributes are known and false otherwise.
341 The recognized non-color attributes are clear, reset, bold, dark, faint,
342 underline, underscore, blink, reverse, and concealed. Clear and reset
343 (reset to default attributes), dark and faint (dim and saturated), and
344 underline and underscore are equivalent, so use whichever is the most
345 intuitive to you. The recognized foreground color attributes are black,
346 red, green, yellow, blue, magenta, cyan, and white. The recognized
347 background color attributes are on_black, on_red, on_green, on_yellow,
348 on_blue, on_magenta, on_cyan, and on_white. Case is not significant.
350 Note that not all attributes are supported by all terminal types, and some
351 terminals may not support any of these sequences. Dark and faint, blink,
352 and concealed in particular are frequently not implemented.
354 Attributes, once set, last until they are unset (by sending the attribute
355 C<clear> or C<reset>). Be careful to do this, or otherwise your attribute
356 will last after your script is done running, and people get very annoyed
357 at having their prompt and typing changed to weird colors.
359 As an aid to help with this, colored() takes a scalar as the first
360 argument and any number of attribute strings as the second argument and
361 returns the scalar wrapped in escape codes so that the attributes will be
362 set as requested before the string and reset to normal after the string.
363 Alternately, you can pass a reference to an array as the first argument,
364 and then the contents of that array will be taken as attributes and color
365 codes and the remainder of the arguments as text to colorize.
367 Normally, colored() just puts attribute codes at the beginning and end of
368 the string, but if you set $Term::ANSIColor::EACHLINE to some string, that
369 string will be considered the line delimiter and the attribute will be set
370 at the beginning of each line of the passed string and reset at the end of
371 each line. This is often desirable if the output contains newlines and
372 you're using background colors, since a background color that persists
373 across a newline is often interpreted by the terminal as providing the
374 default background color for the next line. Programs like pagers can also
375 be confused by attributes that span lines. Normally you'll want to set
376 $Term::ANSIColor::EACHLINE to C<"\n"> to use this feature.
378 =head2 Constant Interface
380 Alternately, if you import C<:constants>, you can use the constants CLEAR,
381 RESET, BOLD, DARK, FAINT, UNDERLINE, UNDERSCORE, BLINK, REVERSE,
382 CONCEALED, BLACK, RED, GREEN, YELLOW, BLUE, MAGENTA, CYAN, WHITE,
383 ON_BLACK, ON_RED, ON_GREEN, ON_YELLOW, ON_BLUE, ON_MAGENTA, ON_CYAN, and
384 ON_WHITE directly. These are the same as color('attribute') and can be
385 used if you prefer typing:
387 print BOLD BLUE ON_WHITE "Text", RESET, "\n";
391 print colored ("Text", 'bold blue on_white'), "\n";
393 (Note that the newline is kept separate to avoid confusing the terminal as
394 described above since a background color is being used.)
396 When using the constants, if you don't want to have to remember to add the
397 C<, RESET> at the end of each print line, you can set
398 $Term::ANSIColor::AUTORESET to a true value. Then, the display mode will
399 automatically be reset if there is no comma after the constant. In other
400 words, with that variable set:
402 print BOLD BLUE "Text\n";
404 will reset the display mode afterward, whereas:
406 print BOLD, BLUE, "Text\n";
408 will not. If you are using background colors, you will probably want to
409 print the newline with a separate print statement to avoid confusing the
412 The subroutine interface has the advantage over the constants interface in
413 that only two subroutines are exported into your namespace, versus
414 twenty-two in the constants interface. On the flip side, the constants
415 interface has the advantage of better compile time error checking, since
416 misspelled names of colors or attributes in calls to color() and colored()
417 won't be caught until runtime whereas misspelled names of constants will
418 be caught at compile time. So, pollute your namespace with almost two
419 dozen subroutines that you may not even use that often, or risk a silly
420 bug by mistyping an attribute. Your choice, TMTOWTDI after all.
422 =head2 The Color Stack
424 As of Term::ANSIColor 2.0, you can import C<:pushpop> and maintain a stack
425 of colors using PUSHCOLOR, POPCOLOR, and LOCALCOLOR. PUSHCOLOR takes the
426 attribute string that starts its argument and pushes it onto a stack of
427 attributes. POPCOLOR removes the top of the stack and restores the
428 previous attributes set by the argument of a prior PUSHCOLOR. LOCALCOLOR
429 surrounds its argument in a PUSHCOLOR and POPCOLOR so that the color
432 When using PUSHCOLOR, POPCOLOR, and LOCALCOLOR, it's particularly
433 important to not put commas between the constants.
435 print PUSHCOLOR BLUE "Text\n";
437 will correctly push BLUE onto the top of the stack.
439 print PUSHCOLOR, BLUE, "Text\n"; # wrong!
441 will not, and a subsequent pop won't restore the correct attributes.
442 PUSHCOLOR pushes the attributes set by its argument, which is normally a
443 string of color constants. It can't ask the terminal what the current
450 =item Bad escape sequence %s
452 (F) You passed an invalid ANSI escape sequence to uncolor().
454 =item Bareword "%s" not allowed while "strict subs" in use
456 (F) You probably mistyped a constant color name such as:
458 $Foobar = FOOBAR . "This line should be blue\n";
462 @Foobar = FOOBAR, "This line should be blue\n";
464 This will only show up under use strict (another good reason to run under
467 =item Invalid attribute name %s
469 (F) You passed an invalid attribute name to either color() or colored().
471 =item Name "%s" used only once: possible typo
473 (W) You probably mistyped a constant color name such as:
475 print FOOBAR "This text is color FOOBAR\n";
477 It's probably better to always use commas after constant names in order to
478 force the next error.
480 =item No comma allowed after filehandle
482 (F) You probably mistyped a constant color name such as:
484 print FOOBAR, "This text is color FOOBAR\n";
486 Generating this fatal compile error is one of the main advantages of using
487 the constants interface, since you'll immediately know if you mistype a
490 =item No name for escape sequence %s
492 (F) The ANSI escape sequence passed to uncolor() contains escapes which
493 aren't recognized and can't be translated to names.
501 =item ANSI_COLORS_DISABLED
503 If this environment variable is set, all of the functions defined by this
504 module (color(), colored(), and all of the constants not previously used
505 in the program) will not output any escape sequences and instead will just
506 return the empty string or pass through the original text as appropriate.
507 This is intended to support easy use of scripts using this module on
508 platforms that don't support ANSI escape sequences.
510 For it to have its proper effect, this environment variable must be set
511 before any color constants are used in the program.
517 It would be nice if one could leave off the commas around the constants
518 entirely and just say:
520 print BOLD BLUE ON_WHITE "Text\n" RESET;
522 but the syntax of Perl doesn't allow this. You need a comma after the
523 string. (Of course, you may consider it a bug that commas between all the
524 constants aren't required, in which case you may feel free to insert
525 commas unless you're using $Term::ANSIColor::AUTORESET or
528 For easier debugging, you may prefer to always use the commas when not
529 setting $Term::ANSIColor::AUTORESET or PUSHCOLOR/POPCOLOR so that you'll
530 get a fatal compile error rather than a warning.
534 The codes generated by this module are standard terminal control codes,
535 complying with ECMA-048 and ISO 6429 (generally referred to as "ANSI
536 color" for the color codes). The non-color control codes (bold, dark,
537 italic, underline, and reverse) are part of the earlier ANSI X3.64
538 standard for control sequences for video terminals and peripherals.
540 Note that not all displays are ISO 6429-compliant, or even X3.64-compliant
541 (or are even attempting to be so). This module will not work as expected
542 on displays that do not honor these escape sequences, such as cmd.exe,
543 4nt.exe, and command.com under either Windows NT or Windows 2000. They
544 may just be ignored, or they may display as an ESC character followed by
545 some apparent garbage.
547 Jean Delvare provided the following table of different common terminal
548 emulators and their support for the various attributes and others have
549 helped me flesh it out:
551 clear bold faint under blink reverse conceal
552 ------------------------------------------------------------------------
553 xterm yes yes no yes yes yes yes
554 linux yes yes yes bold yes yes no
555 rxvt yes yes no yes bold/black yes no
556 dtterm yes yes yes yes reverse yes yes
557 teraterm yes reverse no yes rev/red yes no
558 aixterm kinda normal no yes no yes yes
559 PuTTY yes color no yes no yes no
560 Windows yes no no no no yes no
561 Cygwin SSH yes yes no color color color yes
562 Mac Terminal yes yes no yes yes yes yes
564 Windows is Windows telnet, Cygwin SSH is the OpenSSH implementation under
565 Cygwin on Windows NT, and Mac Terminal is the Terminal application in Mac
566 OS X. Where the entry is other than yes or no, that emulator displays the
567 given attribute as something else instead. Note that on an aixterm, clear
568 doesn't reset colors; you have to explicitly set the colors back to what
569 you want. More entries in this table are welcome.
571 Note that codes 3 (italic), 6 (rapid blink), and 9 (strike-through) are
572 specified in ANSI X3.64 and ECMA-048 but are not commonly supported by
573 most displays and emulators and therefore aren't supported by this module
574 at the present time. ECMA-048 also specifies a large number of other
575 attributes, including a sequence of attributes for font changes, Fraktur
576 characters, double-underlining, framing, circling, and overlining. As
577 none of these attributes are widely supported or useful, they also aren't
578 currently supported by this module.
582 ECMA-048 is available on-line (at least at the time of this writing) at
583 L<http://www.ecma-international.org/publications/standards/ECMA-048.HTM>.
585 ISO 6429 is available from ISO for a charge; the author of this module
586 does not own a copy of it. Since the source material for ISO 6429 was
587 ECMA-048 and the latter is available for free, there seems little reason
588 to obtain the ISO standard.
590 The current version of this module is always available from its web site
591 at L<http://www.eyrie.org/~eagle/software/ansicolor/>. It is also part of
592 the Perl core distribution as of 5.6.0.
596 Original idea (using constants) by Zenin, reimplemented using subs by Russ
597 Allbery <rra@stanford.edu>, and then combined with the original idea by
598 Russ with input from Zenin. Russ Allbery now maintains this module.
600 =head1 COPYRIGHT AND LICENSE
602 Copyright 1996, 1997, 1998, 2000, 2001, 2002, 2005, 2006, 2008, 2009 Russ
603 Allbery <rra@stanford.edu> and Zenin. This program is free software; you
604 may redistribute it and/or modify it under the same terms as Perl itself.
606 PUSHCOLOR, POPCOLOR, and LOCALCOLOR were contributed by openmethods.com