Crayon Language Files
By Aram Kocharyan, http://aramk.com/
Known Elements
These are known, recognised and highlighted by Crayon. You can defined others, but if you want to highlight them, you must add your custom CSS class into a Theme file. The CSS classes are in square brackets, but have a "crayon-" prefix added to them to avoid conflicts.
COMMENT [c]STRING [s]PREPROCESSOR [p]TAG [ta]KEYWORD [k]STATEMENT [st]RESERVED [r]TYPE [t]MODIFIER [m]
IDENTIFIER [i]ENTITY [e]VARIABLE [v]
CONSTANT [cn]OPERATOR [o]SYMBOL [sy]NOTATION [n]FADED [f]HTML_CHAR [h]
Rules
Global
- Whitespace must be used to separate element names, css classes and regex
 - Must be defined on a single line
 
Elements
- Defined as 
ELEMENT_NAME [css] REGEXon a single line, in that order only - Names cannot contain whitespace (must match 
[-_a-zA-Z]+[-_a-zA-Z0-9]*). - When defining an unknown element, you can specify a fallback with a colon:
- e.g. 
MAGIC_WORD:KEYWORD [mg] \bmagic|words|here\b - If the Theme doesn't support the '.mg' class, it will still highlight using the 
KEYWORDclass from the Known Elements section. - Add support for the '.mg' class by adding it at the bottom of the Theme CSS file, after the fallback
 
 - e.g. 
 - If duplicate exists, it replaces previous
 
CSS
- CSS classes are defined in [square brackets], they are optional.
 - No need to use '.' in class name. All characters are converted to lowercase and dots removed.
 - If you use a space, then two classes are applied to the element matches e.g. [first second]
 - If not specified, either default is used (if element is known), or element name is used
 - Class can be applied to multiple elements
 - Class should be valid: 
[-_a-zA-Z]+[-_a-zA-Z0-9]* - If class is invalid, element is still parsed, error reported
 
Regex
- Written as per normal, without delimiters or escaping
 - Applied in the order they appear in the file. If language has reserved keywords, these should be higher than variables
 - Whitespace around regex is ignored - only first character to last forms regex
 - If single space is intended, use \s to avoid conflict with whitespace used for separation e.g. 
TEST [t] \s\s\shello 
Comments
- can be added to this file using 
#,//or/* */ //,#and/*must be the first non-whitespace characters on that line- The 
*/must be on a line by itself 
Special Functions
- Written inside regex, replaced by their outputs when regex is parsed.
 
(?alt:file.txt)
- Import lines from a file and separate with alternation. e.g. 
catdog|dog|cat - File should list words from longest to shortest to avoid clashes
 
(?default) or (?default:element_name)
- Substitute regex with Default language's regex for that element, or a specific element given after a colon.
 
(?html:somechars)
- Convert somechars to html entities. e.g. 
(?html:<>"'&)becomes<>"&. 
Aliases
The aliases.txt contains aliases in the following structure. They are case insensitive:
Format: id alias1 alias2 ...
Example: c# cs csharp
Specifying the alias will use the original language, though it's recommended to use the original if manually specifying the language to reduce confusion and length.
Extensions
Crayon can autodetect a language when highlighting local or remote files with extensions. The extensions.txt file uses the following format:
Format: ID EXTENSION1 EXTENSION2 ...
Example: python py pyw pyc pyo pyd
Delimiters
Certain languages have tags which separate content in that language with that of another. An example is PHP's <?php ?> tags and the <script> and <style> tags in XHTML and CSS. The delimiters.txt file contains regex to capture delimiters that allow code with  mixed highlighting. The format of these is:
Format: id REGEX1 REGEX2 ...
Example: php <\?(?:php)?.*?\?\>