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(elisp)Syntax Descriptors

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Syntax Descriptors
==================

   This section describes the syntax classes and flags that denote the
syntax of a character, and how they are represented as a "syntax
descriptor", which is a Lisp string that you pass to
`modify-syntax-entry' to specify the syntax you want.

   The syntax table specifies a syntax class for each character.  There
is no necessary relationship between the class of a character in one
syntax table and its class in any other table.

   Each class is designated by a mnemonic character, which serves as the
name of the class when you need to specify a class.  Usually the
designator character is one that is often assigned that class; however,
its meaning as a designator is unvarying and independent of what syntax
that character currently has.  Thus, `\' as a designator character
always gives "escape character" syntax, regardless of what syntax `\'
currently has.

   A syntax descriptor is a Lisp string that specifies a syntax class, a
matching character (used only for the parenthesis classes) and flags.
The first character is the designator for a syntax class.  The second
character is the character to match; if it is unused, put a space there.
Then come the characters for any desired flags.  If no matching
character or flags are needed, one character is sufficient.

   For example, the syntax descriptor for the character `*' in C mode
is `. 23' (i.e., punctuation, matching character slot unused, second
character of a comment-starter, first character of a comment-ender),
and the entry for `/' is `. 14' (i.e., punctuation, matching character
slot unused, first character of a comment-starter, second character of
a comment-ender).

Syntax Class Table

Table of syntax classes.

Syntax Flags

Additional flags each character can have.