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).
+
+>>> I think I hadn't realized what you were doing there. The order
+>>> for unnamed parameters can in fact be relied on.
+>>>
+>>> --[[Joey]]
+
+>> 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.
+
+---
+
+And here is RC2 of that plugin. I've changed a plugin syntax, because the old
+seems to be too enigmatic and it was hard to me to handle unnamed parameters
+in not hardcoded way. I hope that my changes are acceptable for you.
+Of course, I'm open for discussion or exchange of ideas :) --[[Paweł|ptecza]]
+
+> One question, why the 2px padding for span.color? --[[Joey]]
+
+>> Sorry for a long silence, but I had Internet free summer holiday :)
+>> I did that, because backgrounded text without any padding looks
+>> strange for me ;) You can remove it if you don't like that padding.
+>> --[[Paweł|ptecza]]
+
+>>> Joey, will you add that plugin to Ikiwiki 2.61? :) --[[Paweł|ptecza]]
+
+>>>> I also had a long net-free summer holiday. :-) The [[patch]] is
+>>>> ready for integration (made a few minor changes). Is this GPL 2?
+>>>> --[[Joey]]
+
+>>>>> No problem. I guessed it, because I've not seen your commits
+>>>>> at [[RecentChanges]] page in last days and I subscribe your
+>>>>> [blog](http://kitenet.net/~joey/blog/entry/vacation/) :D
+>>>>> It's GPL-2+ like your Ikiwiki and the most external plugins.
+>>>>> --[[Paweł|ptecza]]
+
+ --- /dev/null 2008-06-21 02:02:15.000000000 +0200
+ +++ color.pm 2008-07-27 14:58:12.000000000 +0200
+ @@ -0,0 +1,69 @@
+ +#!/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 => "format", id => "color", call => \&format);
+ +}
+ +
+ +sub preserve_style ($$$) {
+ + my $foreground = shift;
+ + my $background = shift;
+ + my $text = shift;
+ +
+ + $foreground = defined $foreground ? lc($foreground) : '';
+ + $background = defined $background ? lc($background) : '';
+ + $text = '' unless (defined $text);
+ +
+ + # Validate colors. Only color name or color code are valid.
+ + $foreground = '' unless ($foreground &&
+ + ($foreground =~ /^[a-z]+$/ || $foreground =~ /^#[0-9a-f]{3,6}$/));
+ + $background = '' unless ($background &&
+ + ($background =~ /^[a-z]+$/ || $background =~ /^#[0-9a-f]{3,6}$/));
+ +
+ + my $preserved = '';
+ + $preserved .= '<span class="color">';
+ + $preserved .= 'color: '.$foreground if ($foreground);
+ + $preserved .= '; ' if ($foreground && $background);
+ + $preserved .= 'background-color: '.$background if ($background);
+ + $preserved .= '</span>';
+ + $preserved .= '<span class="colorend">'.$text.'</span>';
+ +
+ + return $preserved;
+ +
+ +}
+ +
+ +sub replace_preserved_style ($) {
+ + my $content = shift;
+ +
+ + $content =~ s!<span class="color">((color: ([a-z]+|\#[0-9a-f]{3,6})?)?((; )?(background-color: ([a-z]+|\#[0-9a-f]{3,6})?)?)?)</span>!<span class="color" style="$1">!g;
+ + $content =~ s!<span class="colorend">!!g;
+ +
+ + return $content;
+ +}
+ +
+ +sub preprocess (@) {
+ + my %params = @_;
+ +
+ + # Preprocess the text to expand any preprocessor directives
+ + # embedded inside it.
+ + $params{text} = IkiWiki::preprocess($params{page}, $params{destpage},
+ + IkiWiki::filter($params{page}, $params{destpage}, $params{text}));
+ +
+ + return preserve_style($params{foreground}, $params{background}, $params{text});
+ +}
+ +
+ +sub format (@) {
+ + my %params = @_;
+ +
+ + $params{content} = replace_preserved_style($params{content});
+ + return $params{content};
+ +}
+ +
+ +1
+ --- /dev/null 2008-06-21 02:02:15.000000000 +0200
+ +++ color.mdwn 2008-07-27 15:04:42.000000000 +0200
+ @@ -0,0 +1,25 @@
+ +\[[!template id=plugin name=color core=0 author="[[ptecza]]"]]
+ +
+ +This plugin can be used to color a piece of text on a page.
+ +It can be used to set the foreground and/or background color of the text.
+ +
+ +You can use a color name (e.g. `white`) or HTML code (e.g. `#ffffff`)
+ +to define colors.
+ +
+ +Below are a few examples:
+ +
+ + \[[!color foreground=white background=#ff0000 text="White text on red background"]]
+ +
+ +In the above example, the foreground color is defined as a word, while the background color is defined as a HTML
+ +color code.
+ +
+ + \[[!color foreground=white text="White text on default color background"]]
+ +
+ +The background color is missing, so the text is displayed on default background.
+ +
+ + \[[!color background=#ff0000 text="Default color text on red background"]]
+ +
+ +The foreground is missing, so the text has the default foreground color.
+ --- style.css-orig 2008-07-27 15:12:39.000000000 +0200
+ +++ style.css 2008-07-27 15:15:06.000000000 +0200
+ @@ -333,3 +333,7 @@
+ background: #eee;
+ color: black !important;
+ }
+ +
+ +span.color {
+ + padding: 2px;
+ +}
+
+[[done]]