Each element in a user-level keywords list should have one of these forms:
MATCHER
- (MATCHER . MATCH)
+ (MATCHER . SUBEXP)
(MATCHER . FACENAME)
(MATCHER . HIGHLIGHT)
(MATCHER HIGHLIGHT ...)
MATCH-HIGHLIGHT should be of the form:
- (MATCH FACENAME [OVERRIDE [LAXMATCH]])
+ (SUBEXP FACENAME [OVERRIDE [LAXMATCH]])
-MATCH is the subexpression of MATCHER to be highlighted. FACENAME is an
-expression whose value is the face name to use. Face default attributes
-can be modified via \\[customize]. Instead of a face, FACENAME can
-evaluate to a property list of the form (face FACE PROP1 VAL1 PROP2 VAL2 ...)
+SUBEXP is the number of the subexpression of MATCHER to be highlighted.
+
+FACENAME is an expression whose value is the face name to use.
+Instead of a face, FACENAME can evaluate to a property list
+of the form (face FACE PROP1 VAL1 PROP2 VAL2 ...)
in which case all the listed text-properties will be set rather than
just FACE. In such a case, you will most likely want to put those
properties in `font-lock-extra-managed-props' or to override
be overwritten. If `keep', only parts not already fontified are highlighted.
If `prepend' or `append', existing fontification is merged with the new, in
which the new or existing fontification, respectively, takes precedence.
-If LAXMATCH is non-nil, no error is signaled if there is no MATCH in MATCHER.
+If LAXMATCH is non-nil, that means don't signal an error if there is
+no match for SUBEXP in MATCHER.
For example, an element of the form highlights (if not already highlighted):
should return a face. This is normally set via `font-lock-defaults'.")
(defvar font-lock-syntactic-keywords nil
- "A list of the syntactic keywords to highlight.
-Can be the list or the name of a function or variable whose value is the list.
+ "A list of the syntactic keywords to put syntax properties on.
+The value can be the list itself, or the name of a function or variable
+whose value is the list.
+
See `font-lock-keywords' for a description of the form of this list;
-the differences are listed below. MATCH-HIGHLIGHT should be of the form:
+only the differences are stated here. MATCH-HIGHLIGHT should be of the form:
- (MATCH SYNTAX OVERRIDE LAXMATCH)
+ (SUBEXP SYNTAX OVERRIDE LAXMATCH)
where SYNTAX can be a string (as taken by `modify-syntax-entry'), a syntax
table, a cons cell (as returned by `string-to-syntax') or an expression whose
value is such a form. OVERRIDE cannot be `prepend' or `append'.
-For example, an element of the form highlights syntactically:
+Here are two examples of elements of `font-lock-syntactic-keywords'
+and what they do:
(\"\\\\$\\\\(#\\\\)\" 1 \".\")
- a hash character when following a dollar character, with a SYNTAX of
- \".\" (meaning punctuation syntax). Assuming that the buffer syntax table does
- specify hash characters to have comment start syntax, the element will only
- highlight hash characters that do not follow dollar characters as comments
- syntactically.
+ gives a hash character punctuation syntax (\".\") when following a
+ dollar-sign character. Hash characters in other contexts will still
+ follow whatever the syntax table says about the hash character.
(\"\\\\('\\\\).\\\\('\\\\)\"
(1 \"\\\"\")
(2 \"\\\"\"))
- both single quotes which surround a single character, with a SYNTAX of
- \"\\\"\" (meaning string quote syntax). Assuming that the buffer syntax table
- does not specify single quotes to have quote syntax, the element will only
- highlight single quotes of the form 'c' as strings syntactically.
- Other forms, such as foo'bar or 'fubar', will not be highlighted as strings.
+ gives a pair single-quotes, which surround a single character, a SYNTAX of
+ \"\\\"\" (meaning string quote syntax). Single-quote characters in other
+ contexts will not be affected.
This is normally set via `font-lock-defaults'.")