/* Part of SWI-Prolog Author: Jan Wielemaker E-mail: J.Wielemaker@vu.nl WWW: http://www.swi-prolog.org Copyright (c) 2010-2018, VU University Amsterdam CWI, Amsterdam All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ :- module(ansi_term, [ ansi_format/3 % +Attr, +Format, +Args ]). :- use_module(library(apply)). :- use_module(library(error)). /** Print decorated text to ANSI consoles This library allows for exploiting the color and attribute facilities of most modern terminals using ANSI escape sequences. This library provides the following: - ansi_format/3 allows writing messages to the terminal with ansi attributes. - It defines the hook prolog:message_line_element/2, which provides ansi attributes for print_message/2. @see http://en.wikipedia.org/wiki/ANSI_escape_code */ :- create_prolog_flag(color_term, true, [type(boolean)]). :- meta_predicate keep_line_pos(+, 0). :- multifile user:message_property/2. %! ansi_format(+Attributes, +Format, +Args) is det. % % Format text with ANSI attributes. This predicate behaves as % format/2 using Format and Args, but if the =current_output= is a % terminal, it adds ANSI escape sequences according to Attributes. % For example, to print a text in bold cyan, do % % == % ?- ansi_format([bold,fg(cyan)], 'Hello ~w', [world]). % == % % Attributes is either a single attribute or a list thereof. The % attribute names are derived from the ANSI specification. See the % source for sgr_code/2 for details. Some commonly used attributes % are: % % - bold % - underline % - fg(Color), bg(Color), hfg(Color), hbg(Color) % % Defined color constants are below. =default= can be used to % access the default color of the terminal. % % - black, red, green, yellow, blue, magenta, cyan, white % % ANSI sequences are sent if and only if % % - The =current_output= has the property tty(true) (see % stream_property/2). % - The Prolog flag =color_term= is =true=. ansi_format(Attr, Format, Args) :- ansi_format(current_output, Attr, Format, Args). ansi_format(Stream, Attr, Format, Args) :- stream_property(Stream, tty(true)), current_prolog_flag(color_term, true), !, ( is_list(Attr) -> maplist(sgr_code_ex, Attr, Codes), atomic_list_concat(Codes, ;, Code) ; sgr_code_ex(Attr, Code) ), format(string(Fmt), '\e[~~wm~w\e[0m', [Format]), format(Stream, Fmt, [Code|Args]), flush_output. ansi_format(Stream, _Attr, Format, Args) :- format(Stream, Format, Args). sgr_code_ex(Attr, Code) :- sgr_code(Attr, Code), !. sgr_code_ex(Attr, _) :- domain_error(sgr_code, Attr). %! sgr_code(+Name, -Code) % % True when code is the Select Graphic Rendition code for Name. % The defined names are given below. Note that most terminals only % implement this partially. % % | reset | all attributes off | % | bold | | % | faint | | % | italic | | % | underline | | % | blink(slow) | | % | blink(rapid) | | % | negative | | % | conceal | | % | crossed_out | | % | font(primary) | | % | font(N) | Alternate font (1..8) | % | fraktur | | % | underline(double) | | % | intensity(normal) | | % | fg(Name) | Color name | % | bg(Name) | Color name | % | framed | | % | encircled | | % | overlined | | % | ideogram(underline) | | % | right_side_line | | % | ideogram(underline(double)) | | % | right_side_line(double) | | % | ideogram(overlined) | | % | left_side_line | | % | ideogram(stress_marking) | | % | -Off | Switch attributes off | % | hfg(Name) | Color name | % | hbg(Name) | Color name | % % @see http://en.wikipedia.org/wiki/ANSI_escape_code sgr_code(reset, 0). sgr_code(bold, 1). sgr_code(faint, 2). sgr_code(italic, 3). sgr_code(underline, 4). sgr_code(blink(slow), 5). sgr_code(blink(rapid), 6). sgr_code(negative, 7). sgr_code(conceal, 8). sgr_code(crossed_out, 9). sgr_code(font(primary), 10) :- !. sgr_code(font(N), C) :- C is 10+N. sgr_code(fraktur, 20). sgr_code(underline(double), 21). sgr_code(intensity(normal), 22). sgr_code(fg(Name), C) :- ansi_color(Name, N), C is N+30. sgr_code(bg(Name), C) :- !, ansi_color(Name, N), C is N+40. sgr_code(framed, 51). sgr_code(encircled, 52). sgr_code(overlined, 53). sgr_code(ideogram(underline), 60). sgr_code(right_side_line, 60). sgr_code(ideogram(underline(double)), 61). sgr_code(right_side_line(double), 61). sgr_code(ideogram(overlined), 62). sgr_code(left_side_line, 62). sgr_code(ideogram(stress_marking), 64). sgr_code(-X, Code) :- off_code(X, Code). sgr_code(hfg(Name), C) :- ansi_color(Name, N), C is N+90. sgr_code(hbg(Name), C) :- !, ansi_color(Name, N), C is N+100. off_code(italic_and_franktur, 23). off_code(underline, 24). off_code(blink, 25). off_code(negative, 27). off_code(conceal, 28). off_code(crossed_out, 29). off_code(framed, 54). off_code(overlined, 55). ansi_color(black, 0). ansi_color(red, 1). ansi_color(green, 2). ansi_color(yellow, 3). ansi_color(blue, 4). ansi_color(magenta, 5). ansi_color(cyan, 6). ansi_color(white, 7). ansi_color(default, 9). /******************************* * HOOK * *******************************/ %! prolog:message_line_element(+Stream, +Term) is semidet. % % Hook implementation that deals with ansi(+Attr, +Fmt, +Args) in % message specifications. prolog:message_line_element(S, ansi(Attr, Fmt, Args)) :- ansi_format(S, Attr, Fmt, Args). prolog:message_line_element(S, ansi(Attr, Fmt, Args, Ctx)) :- ansi_format(S, Attr, Fmt, Args), ( nonvar(Ctx), Ctx = ansi(_, RI-RA) -> keep_line_pos(S, format(S, RI, RA)) ; true ). prolog:message_line_element(S, begin(Level, Ctx)) :- level_attrs(Level, Attr), stream_property(S, tty(true)), current_prolog_flag(color_term, true), !, ( is_list(Attr) -> maplist(sgr_code, Attr, Codes), atomic_list_concat(Codes, ;, Code) ; sgr_code(Attr, Code) ), keep_line_pos(S, format(S, '\e[~wm', [Code])), Ctx = ansi('\e[0m', '\e[0m\e[~wm'-[Code]). prolog:message_line_element(S, end(Ctx)) :- nonvar(Ctx), Ctx = ansi(Reset, _), keep_line_pos(S, write(S, Reset)). level_attrs(Level, Attrs) :- user:message_property(Level, color(Attrs)). level_attrs(informational, fg(green)). level_attrs(information, fg(green)). level_attrs(debug(_), fg(blue)). level_attrs(warning, fg(red)). level_attrs(error, [fg(red),bold]). keep_line_pos(S, G) :- stream_property(S, position(Pos)), !, stream_position_data(line_position, Pos, LPos), G, set_stream(S, line_position(LPos)). keep_line_pos(_, G) :- G.