Common syntax classes

TODO: I need to expand this, but for now I just want to document the
common syntax classes...

General classes

=Idle

• The default coloring. Normal text.

=Ident

• Identifiers; this is any identifier as opposed to definitions.

=Bad

• Used to indicate a parse error. Generally red or yellow text or background.

Specific identifiers

=DefinedIdent +Ident

• An identifier that is being defined at this point. This might be a class,
  function, or struct (... or union or enum, etc).

=DefinedFunction +DefinedIdent

• More specific than DefinedIdent. This is the identifier in a function
  definition.

=DefinedType +DefinedIdent

• More specific than DefinedIdent. This is the identifier in a type
  definition.

=Label +DefinedIdent

• Jump labels, case statements.

Preprocessor

=Preproc

• Preprocessor directives.

=Precond +Preproc

• Conditional preprocessor directives, e.g. #if, #ifdef, #else, #endif, etc

=Define +DefinedIdent +Preproc

• Preprocessor definitions. This is the identifier that is being defined.

=Include +Preproc

• Include directives

=IncLocal +String +Preproc

• The file being included if it is local, e.g. quoted in C.

=IncSystem +Preproc +Keyword

• The file being included if it is a system include, e.g. angle brackets in
  C.

=Attribute +Define +Preproc

• A decorator in Python, an attribute in Elixir.

Comments

=Comment

• Comments.

=TODO +Comment

• Flags TODO, FIXME, HACK, NOTE, BUG, XXX in comments.

Constants

=Constant

• Base syntax class for any constant.

=Number +Constant

• Numeric constants.

=Boolean +Constant

• true or false

=String +Constant

• String constants

=Escape

• Escape characters. Generally line continuations or the base for special
  characters in strings.

=StringEscape +Escape +String

• Special characters in a string: \n, %s, etc

=Character +String +Constant

• Literal character constants

=CharacterEscape +StringEscape +Character

• Special character in a character constant: \n, %s, etc

=Regex +String

• A literal regular expression

=Variable +Escape

• A variable in languages that prefix it, e.g. $foo or %bar%

=Docstring +Comment

• Documentation strings

=DocstringLabel +Docstring

• TODO in docstrings in Python. Should be renamed.

=DocEscape +Escape +Docstring

• Escapes in documentation strings.

=StringVariable +StringEscape

• A variable interpolated in a string

Language constructs

=Keyword

• Base class for a reserved keyword in the language

=Statement +Keyword

• A statement keyword, e.g. for, if, switch, etc in C.

=Loop +Statement

• A statement keyword that defines a loop.

=Conditional +Statement

• A statement keyword that definese a conditional.

=Operator +Keyword

• An operator keyword. Different languages use this one differently and I'm
  not sure what is the correct usage. Should it be all operators or only
  those that have names. E.g., in python this would include in, is, etc
  but not +, *, -, /, etc. Those are typically handled by Control.

=Type

• A builtin type

=StorageClass +Type +Keyword

• Keywords that modify the storage class, e.g. volatile, static,
  const, etc.

=Structure +Type +Keyword

• Keywords that declare aggregate data types, struct, class, etc.

=Brace

• Braces, in languages that use those to delimit blocks: {, }

=Control

• Other symbolic characters that have meaning in the language, generally
  operators.

Misc/special

(Yes, the bases are weird for diff)

=diff.DelLine +Escape

• Deleted line in a diff

=diff.AddLine +DefinedIdent

• Added line in a diff

=diff.ChgLine +Preproc

• Changed line in a diff

=CppKeyword +Keyword

• Specific to C: a C++ keyword

=Tag +DefinedFunction +DefinedIdent

• Tag edge (< and >) in XML and HTML

=TagName +Tag

• Tag name

=TagEnd +Tag

• End tag (the whole thing)

=Attr +Type

• Attribute name in XML/HTML tag

=Entity     +Escape

• XML and HTML entities

=StringEntity   +StringEscape +Entity

• Entites found inside of attribute values, which are Strings

=Namespace  +Comment

• XML namespace prefixes

More in XML and HTML:
* PIStart, PIBody, PIEnd
* CdataEdge, CdataBody
* Decl