NAME ColorTheme - Color themes SPECIFICATION VERSION 2 VERSION This document describes version 2.1.2 of ColorTheme (from Perl distribution ColorTheme), released on 2020-06-19. DESCRIPTION This document specifies a way to create and use color themes. SPECIFICATION STATUS The series 2.x version is still unstable. API might still change between releases. GLOSSARY color theme Essentially, a mapping of item names and item colors. For example, a color theme for syntax-coloring JSON might be something like: { string => "ffff00", number => "00ffff", comma => "", brace => "", bracket => "", null => "ff0000", true => "00ff00", false => "008000", } An application (in this case, a JSON pretty-printer) will consult the color theme to get the color codes for various items. By using a different color theme which contains the same item names, a user can change the appearance of an application or its output (in terms of color) simply by using another compatible color theme, i.e. color theme which provides color codes for the same items. color theme structure A DefHash which contains the "color theme" and additional data. A simple (static) theme has all its information accessible from the color theme structure. color theme class A Perl module in the "ColorTheme::*" namespace following this specification. A color theme class contains "color theme structure" in its %THEME package variable, as well as some required methods to access the information in the structure. A simple (static) theme has all its information accessible from the color theme structure, so client can actually bypass the methods and access the color theme structure directly. Although it is recommended to always use the methods to access information in the color theme. static color theme A color theme where all the items are specified in the color theme structure. A client can by-pass the method and access %THEME directly. See also: "dynamic color theme". dynamic color theme A color theme where one must call "/list_items" to get all the items, because not all (or any) of the items are specified in the color theme structure. A dynamic color theme can produce items on-demand or transform other color themes, e.g. provide a tint or duotone color effect on an existing theme. When a color theme is dynamic, it must set the property "dynamic" in the color theme structure to true. See also: "static color theme". SPECIFICATION Color theme class A color theme class must be put in "ColorTheme::" namespace. Application-specific color themes should be put under "ColorTheme::MODULE::NAME::*" or "ColorTheme::APP::NAME::*". The color theme class must declare a package hash variable named %THEME containing the color theme structure. It also must provide these methods: * new Usage: my $ctheme_obj = ColorTheme::NAME->new([ %args ]); Constructor. Known arguments will depend on the particular theme class and must be specified in the color theme structure under the "args" key. * get_struct Usage: my $ctheme_struct = ColorTheme::NAME->get_struct; my $ctheme_struct = $ctheme_obj->get_struct; Provide a method way of getting the "color theme structure". Must also work as a static method. A client can also access the %THEME package variable directly. * get_args Usage: my $args = $ctheme_obj->get_args; Provide a method way of getting the arguments to the constructor. The official implementation ColorThemeBase::Constructor stores this in the 'args' key of the hash object, but the proper way to access the arguments should be via this method. * list_items Usage: my @item_names = $theme_class->list_items; my $item_names = $theme_class->list_items; Must return list of item names provided by theq theme. Each item has a color associated with it and the color can be retrieved using "get_color". * get_item_color Usage: my $color = $theme_class->get_item_color($item_name [ , \%args ]); Get color for an item. See "Item color". Color theme structure Color theme structure is a DefHash containing these keys: * v Required. Float. From DefHash. Must be set to 2 (this specification version). * summary String. Optional. From DefHash. * description String. Optional. From DefHash. * args Hash of argument names as keys, and argument specification DefHash as values. The argument specification resembles that specified in Rinci::function. Some of the important or relevant properties: "req", "schema", "default". * dynamic Boolean, optional. Must be set to true if the theme class is dynamic, i.e. the "items" property does not contain all (or even any) of the items of the theme. Client must call "list_items" to list all the items in the theme. * items Required. Hash of item names as keys and item colors as values. See "Item color". Item color The color of an item can be one of three things. First, the simplest, a single RGB value in the form of 6-hexdigit string, e.g. "ffcc00". Second, a DefHash called "item colors hash" containing one or more of these properties: "fg" (foreground RGB color), "bg" (background RGB color), "ansi_fg" (foreground ANSI escape sequence string), "ansi_bg" (background ANSI escape sequence string). It can also contain additional information like "summary" (a summary describing the item), "description", "tags", and so on. Properties like "ansi_fg" and "ansi_bg" are used to support specifying things that are not representable by RGB, e.g. reverse or bold. Third, a coderef which if called is expected to return one of the two formerly mentioned value (RGB string or the "item colors hash"). A coderef cannot return another coderef. Coderef will be called with arguments "($self, $name, \%args)" where $self is the color theme class (from which you can access the color theme structure as well as arguments to the constructor), $name is the item name requested, and "\%args" is hashref to additional, per-item arguments. Allowing coderef as color allows for flexibility, e.g. for doing gradation border color, random color, context-sensitive color, etc. HISTORY Color::Theme is an older specification, superseded by this document. HOMEPAGE Please visit the project's homepage at . SOURCE Source repository is at . BUGS Please report any bugs or feature requests on the bugtracker website When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature. SEE ALSO DefHash AUTHOR perlancar COPYRIGHT AND LICENSE This software is copyright (c) 2020, 2018, 2014 by perlancar@cpan.org. This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.