Recently I've wanted to colour some piece of text on my Ikiwiki page.
It seems that Markdown can do it only using HTML tags, so I used
-<span class="color">foo bar baz</span>.
+`<span class="color">foo bar baz</span>`.
However, in my opinion mixing Markdown syntax and HTML tags is rather ugly,
so maybe we should create a new color plugin to add more color to Ikiwiki ;)
but I don't have a better idea right now.
What do you think about it? --[[Paweł|ptecza]]
+
+> Making a plugin preserve style attributes can be done, it just has to add
+> them after the sanitize step, which strips them. The general method is
+> adding placeholders first, and replacing them with the real html later.
+>
+> The hard thing to me seems to be finding a syntax that is better than a
+> `<span>`. A preprocessor directive is not really any less ugly than html
+> tags, though at least it could play nicely with nested markdown: --[[Joey]]
+>
+> \[[!color red,green """
+> Xmas-colored markdown here
+> """]]
+
+>> I'm glad you like that idea. In my opinion your syntax looks good.
+>> Out of curiosity, why did you used 2 colors in your example? What is HTML
+>> result for it? ;)
+
+>>> I was thinking one would be foreground, the other background. Don't
+>>> know if setting the background makes sense or not.
+
+>> I can try to create that plugin, if you are too busy now. I'm not Perl
+>> hacker, but I wrote a lot of Perl scripts in my life and color plugin
+>> doesn't seem to be very hard task. --[[Paweł|ptecza]]
+
+>> Yes, it's a good intro plugin, have at it! --[[Joey]]
+
+---
+
+This is a RC1 of my `color` plugin. It works for me well, but all your
+comments are very welcome. --[[Paweł|ptecza]]
+
+> Sure, I have a couple.
+
+>> Great! Thank you very much! --[[Paweł|ptecza]]
+
+> The preprocess function is passed named parameters. The hack you have of
+> hardcoding use of `$_[0]` and `$_[2]` can fail at any time.
+
+>> But the problem is that arguments of my plugin don't have a name.
+>> How can I identify them in `params` hash?
+
+>> Similar hardcoded method I've found in `img` plugin :) But only one
+>> argument is not named there (image path).
+
+>> Maybe I shouldn't use so simple plugin syntax? For following syntax
+>> I wouldn't have that problem:
+
+>> \[[!color fg=white bg=red text="White text on red background"]]
+
+> `replace_preserved_style` is passed a single parameter, so its prototype
+> should be `($)`, not `(@)`. Ditt `preserve_style`, it should have
+> `($$)`.
+
+>> OK, it will be fixed.
+
+> The sanitize hook is always passed `$params{content}`, so there should be
+> no reason to check that it exists. Also, it shouldn't be done in a
+> sanitize hook, since html sanitization could run _after_ that santize
+> hook. It should use a format hook.
+
+>> Probably you're right. It was rather paranoid checking ;) Thanks for
+>> the hook hint!
+
+> The preprocess hook needs to call `IkiWiki::preprocess` on the content
+> passed into it if you want to support nesting other preprocessor
+> directives inside the color directive. See `preprocess_toggleable` in the
+> toggle plugin, for example.
+>
+> I'm not a big fan of the dummy text `COLORS { ... } SROLOC;TEXT { ... TXET }`
+> The method used by toggle of using two real `<div>`s seems slightly
+> better. --[[Joey]]
+
+>> I don't like that too, but I didn't have better idea :) Thank you for
+>> the hint! I'll take a look at `toggle` plugin.
+
+ --- /dev/null 2008-07-24 09:38:19.000000000 +0200
+ +++ color.pm 2008-07-25 14:43:15.000000000 +0200
+ @@ -0,0 +1,75 @@
+ +#!/usr/bin/perl
+ +# Ikiwiki text colouring plugin
+ +# Paweł Tęcza <ptecza@net.icm.edu.pl>
+ +package IkiWiki::Plugin::color;
+ +
+ +use warnings;
+ +use strict;
+ +use IkiWiki 2.00;
+ +
+ +sub import { #{{{
+ + hook(type => "preprocess", id => "color", call => \&preprocess);
+ + hook(type => "sanitize", id => "color", call => \&sanitize);
+ +} #}}}
+ +
+ +sub preserve_style(@) { #{{{
+ + my ($colors, $text) = @_;
+ + $colors = '' unless $colors; # foreground and background colors
+ + $text = '' unless $text; # text
+ +
+ + # Check colors
+ + my ($color1, $color2) = ();
+ + $colors = lc($colors); # Regexps on lower case strings are simpler
+ + if ($colors =~ /,/) {
+ + # Probably defined both foreground and background color
+ + ($color1, $color2) = ($colors =~ /(.*),(.*)/);
+ + }
+ + else {
+ + # Probably defined only foreground color
+ + ($color1, $color2) = ($colors, '');
+ + }
+ +
+ + # Validate colors. Only color name or color code are valid.
+ + my ($fg, $bg) = ();
+ + $fg = $color1 if ($color1 &&
+ + ($color1 =~ /^[a-z]+$/ || $color1 =~ /^#[0-9a-f]{3,6}$/));
+ + $bg = $color2 if ($color2 &&
+ + ($color2 =~ /^[a-z]+$/ || $color2 =~ /^#[0-9a-f]{3,6}$/));
+ +
+ + my $preserved = '';
+ + if ($fg || $bg) {
+ + $preserved .= 'COLORS {';
+ + $preserved .= 'color: '.$fg if ($fg);
+ + $preserved .= '; ' if ($fg && $bg);
+ + $preserved .= 'background-color: '.$bg if ($bg);
+ + $preserved .= '} SROLOC;TEXT {'.$text.'} TXET';
+ + }
+ +
+ + return $preserved;
+ +
+ +} #}}}
+ +
+ +sub replace_preserved_style(@) { #{{{
+ + my $content = shift;
+ +
+ + if ($content) {
+ + $content =~ s/COLORS {/<span style="/;
+ + $content =~ s/} SROLOC;TEXT {/">/;
+ + $content =~ s/} TXET/<\/span>/;
+ + }
+ +
+ + return $content;
+ +} #}}}
+ +
+ +sub preprocess (@) { #{{{
+ + return preserve_style($_[0], $_[2]);
+ +} #}}}
+ +
+ +sub sanitize (@) { #{{{
+ + my %params = @_;
+ +
+ + return replace_preserved_style($params{content})
+ + if (exists $params{content})
+ +} #}}}
+ +
+ +1
+ --- /dev/null 2008-07-24 09:38:19.000000000 +0200
+ +++ color.mdwn 2008-07-25 14:50:19.000000000 +0200
+ @@ -0,0 +1,31 @@
+ +\[[!template id=plugin name=color core=0 author="[[Paweł Tęcza|ptecza]]"]]
+ +
+ +This plugin can be used to color a piece of text on Ikiwiki page.
+ +It's possible setting foreground and/or background color of the text.
+ +
+ +The plugin syntax is very simple. You only need to type name (e.g. `white`)
+ +or HTML code of colors (e.g. `#ffffff`) and a text you want to color.
+ +The colors should by separated using a comma character.
+ +
+ +Below are a few examples:
+ +
+ + \[[!color white,#ff0000 "White text on red background"]]
+ +
+ +Foreground color is defined as a word, background color is defined as HTML
+ +color code.
+ +
+ + \[[!color white "White text on default color background"]]
+ +
+ +Foreground color is default color if only one color was typed and a comma
+ +character is missing.
+ +
+ + \[[!color white, "White text on default color background"]]
+ +
+ +Background color is missing, so the text is displayed on default background.
+ +
+ + \[[!color ,#ff0000 "Default color text on red background"]]
+ +
+ +Foreground is missing, so the text has default color.