


Term::ANSIColor(3Perl Programmers Reference GuTerm::ANSIColor(3p)


NAME
       Term::ANSIColor - Color screen output using ANSI escape
       sequences

SYNOPSIS
           use Term::ANSIColor;
           print color 'bold blue';
           print "This text is bold blue.\n";
           print color 'reset';
           print "This text is normal.\n";
           print colored ("Yellow on magenta.\n", 'yellow on_magenta');
           print "This text is normal.\n";
           print colored ['yellow on_magenta'], "Yellow on magenta.\n";

           use Term::ANSIColor qw(:constants);
           print BOLD, BLUE, "This text is in bold blue.\n", RESET;

           use Term::ANSIColor qw(:constants);
           $Term::ANSIColor::AUTORESET = 1;
           print BOLD BLUE "This text is in bold blue.\n";
           print "This text is normal.\n";


DESCRIPTION
       This module has two interfaces, one through color() and
       colored() and the other through constants.

       color() takes any number of strings as arguments and con-
       siders them to be space-separated lists of attributes.  It
       then forms and returns the escape sequence to set those
       attributes.  It doesn't print it out, just returns it, so
       you'll have to print it yourself if you want to (this is
       so that you can save it as a string, pass it to something
       else, send it to a file handle, or do anything else with
       it that you might care to).

       The recognized attributes (all of which should be fairly
       intuitive) are clear, reset, dark, bold, underline, under-
       score, blink, reverse, concealed, black, red, green, yel-
       low, blue, magenta, on_black, on_red, on_green, on_yellow,
       on_blue, on_magenta, on_cyan, and on_white.  Case is not
       significant.  Underline and underscore are equivalent, as
       are clear and reset, so use whichever is the most intu-
       itive to you.  The color alone sets the foreground color,
       and on_color sets the background color.

       Note that not all attributes are supported by all terminal
       types, and some terminals may not support any of these
       sequences.  Dark, blink, and concealed in particular are
       frequently not implemented.

       Attributes, once set, last until they are unset (by send-
       ing the attribute "reset").  Be careful to do this, or
       otherwise your attribute will last after your script is



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       done running, and people get very annoyed at having their
       prompt and typing changed to weird colors.

       As an aid to help with this, colored() takes a scalar as
       the first argument and any number of attribute strings as
       the second argument and returns the scalar wrapped in
       escape codes so that the attributes will be set as
       requested before the string and reset to normal after the
       string.  Alternately, you can pass a reference to an array
       as the first argument, and then the contents of that array
       will be taken as attributes and color codes and the
       remainder of the arguments as text to colorize.

       Normally, colored() just puts attribute codes at the
       beginning and end of the string, but if you set
       $Term::ANSIColor::EACHLINE to some string, that string
       will be considered the line delimiter and the attribute
       will be set at the beginning of each line of the passed
       string and reset at the end of each line.  This is often
       desirable if the output is being sent to a program like a
       pager that can be confused by attributes that span lines.
       Normally you'll want to set $Term::ANSIColor::EACHLINE to
       ""\n"" to use this feature.

       Alternately, if you import ":constants", you can use the
       constants CLEAR, RESET, BOLD, DARK, UNDERLINE, UNDERSCORE,
       BLINK, REVERSE, CONCEALED, BLACK, RED, GREEN, YELLOW,
       BLUE, MAGENTA, ON_BLACK, ON_RED, ON_GREEN, ON_YELLOW,
       ON_BLUE, ON_MAGENTA, ON_CYAN, and ON_WHITE directly.
       These are the same as color('attribute') and can be used
       if you prefer typing:

           print BOLD BLUE ON_WHITE "Text\n", RESET;

       to

           print colored ("Text\n", 'bold blue on_white');

       When using the constants, if you don't want to have to
       remember to add the ", RESET" at the end of each print
       line, you can set $Term::ANSIColor::AUTORESET to a true
       value.  Then, the display mode will automatically be reset
       if there is no comma after the constant.  In other words,
       with that variable set:

           print BOLD BLUE "Text\n";

       will reset the display mode afterwards, whereas:

           print BOLD, BLUE, "Text\n";

       will not.

       The subroutine interface has the advantage over the



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       constants interface in that only two subroutines are
       exported into your namespace, versus twenty-two in the
       constants interface.  On the flip side, the constants
       interface has the advantage of better compile time error
       checking, since misspelled names of colors or attributes
       in calls to color() and colored() won't be caught until
       runtime whereas misspelled names of constants will be
       caught at compile time.  So, polute your namespace with
       almost two dozen subroutines that you may not even use
       that often, or risk a silly bug by mistyping an attribute.
       Your choice, TMTOWTDI after all.

DIAGNOSTICS
       Invalid attribute name %s
           (F) You passed an invalid attribute name to either
           color() or colored().

       Name ""%s"" used only once: possible typo
           (W) You probably mistyped a constant color name such
           as:

               print FOOBAR "This text is color FOOBAR\n";

           It's probably better to always use commas after con-
           stant names in order to force the next error.

       No comma allowed after filehandle
           (F) You probably mistyped a constant color name such
           as:

               print FOOBAR, "This text is color FOOBAR\n";

           Generating this fatal compile error is one of the main
           advantages of using the constants interface, since
           you'll immediately know if you mistype a color name.

       Bareword ""%s"" not allowed while ""strict subs"" in use
           (F) You probably mistyped a constant color name such
           as:

               $Foobar = FOOBAR . "This line should be blue\n";

           or:

               @Foobar = FOOBAR, "This line should be blue\n";

           This will only show up under use strict (another good
           reason to run under use strict).

RESTRICTIONS
       It would be nice if one could leave off the commas around
       the constants entirely and just say:

           print BOLD BLUE ON_WHITE "Text\n" RESET;



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       but the syntax of Perl doesn't allow this.  You need a
       comma after the string.  (Of course, you may consider it a
       bug that commas between all the constants aren't required,
       in which case you may feel free to insert commas unless
       you're using $Term::ANSIColor::AUTORESET.)

       For easier debuging, you may prefer to always use the com-
       mas when not setting $Term::ANSIColor::AUTORESET so that
       you'll get a fatal compile error rather than a warning.

NOTES
       Jean Delvare provided the following table of different
       common terminal emulators and their support for the vari-
       ous attributes:

                     clear    bold     dark    under    blink   reverse  conceal
        ------------------------------------------------------------------------
        xterm         yes      yes      no      yes     bold      yes      yes
        linux         yes      yes      yes    bold      yes      yes      no
        rxvt          yes      yes      no      yes  bold/black   yes      no
        dtterm        yes      yes      yes     yes    reverse    yes      yes
        teraterm      yes    reverse    no      yes    rev/red    yes      no
        aixterm      kinda   normal     no      yes      no       yes      yes

       Where the entry is other than yes or no, that emulator
       interpret the given attribute as something else instead.
       Note that on an aixterm, clear doesn't reset colors; you
       have to explicitly set the colors back to what you want.
       More entries in this table are welcome.

AUTHORS
       Original idea (using constants) by Zenin (zenin@best.com),
       reimplemented using subs by Russ Allbery (rra@stan-
       ford.edu), and then combined with the original idea by
       Russ with input from Zenin.






















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