ack/lang/cem/cemcom/class.h

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/*
* (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
* See the copyright notice in the ACK home directory, in the file "Copyright".
*/
1994-06-24 14:02:31 +00:00
/* $Id$ */
1986-03-10 13:07:55 +00:00
/* U S E O F C H A R A C T E R C L A S S E S */
/* As a starter, chars are divided into classes, according to which
token they can be the start of.
At present such a class number is supposed to fit in 4 bits.
*/
#define class(ch) (tkclass[ch])
/* Being the start of a token is, fortunately, a mutual exclusive
property, so, although there are less than 16 classes they can be
packed in 4 bits.
*/
#define STSKIP 0 /* spaces and so on: skipped characters */
#define STNL 1 /* newline character(s): update linenumber etc. */
#define STGARB 2 /* garbage ascii character: not allowed in C */
#define STSIMP 3 /* this character can occur as token in C */
#define STCOMP 4 /* this one can start a compound token in C */
#define STIDF 5 /* being the initial character of an identifier */
#define STCHAR 6 /* the starter of a character constant */
#define STSTR 7 /* the starter of a string */
#define STNUM 8 /* the starter of a numeric constant */
#define STEOI 9 /* End-Of-Information mark */
/* But occurring inside a token is not, so we need 1 bit for each
class. This is implemented as a collection of tables to speed up
the decision whether a character has a special meaning.
*/
#define in_idf(ch) (inidf[ch])
#define is_oct(ch) (isoct[ch])
#define is_dig(ch) (isdig[ch])
#define is_hex(ch) (ishex[ch])
extern char tkclass[];
extern char inidf[], isoct[], isdig[], ishex[];