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move inclusion point of text.h to clean things up a bit -------------------- ChangeLog entries follow: -------------------- src/ChangeLog addition: 2010-03-02 Ben Wing <ben@xemacs.org> * lisp.h: * text.h: Move inclusion point of text.h earlier in lisp.h -- just before the definition of characters, which needs some of the stuff in text.h. With text.h later, some basic character properties had to be defined in lisp.h -- put them back into text.h where they belong. Move some text in lisp.h at the point of text.h inclusion into text.h -- it serves as a mini-introduction.
author Ben Wing <ben@xemacs.org>
date Tue, 02 Mar 2010 06:19:51 -0600
parents 22179cd0fe15
children 6c6d78781d59
comparison
equal deleted inserted replaced
5091:ed624ab64583 5092:3aa3888729c3
45 char *strupr (char *); 45 char *strupr (char *);
46 #endif 46 #endif
47 47
48 BEGIN_C_DECLS 48 BEGIN_C_DECLS
49 49
50 /************************************************************************/
51 /* A short intro to the format of text and of characters */
52 /************************************************************************/
53
54 /*
55 "internally formatted text" and the term "internal format" in
56 general are likely to refer to the format of text in buffers and
57 strings; "externally formatted text" and the term "external format"
58 refer to any text format used in the O.S. or elsewhere outside of
59 XEmacs. The format of text and of a character are related and
60 there must be a one-to-one relationship (hopefully through a
61 relatively simple algorithmic means of conversion) between a string
62 of text and an equivalent array of characters, but the conversion
63 between the two is NOT necessarily trivial.
64
65 In a non-Mule XEmacs, allowed characters are numbered 0 through
66 255, where no fixed meaning is assigned to them, but (when
67 representing text, rather than bytes in a binary file) in practice
68 the lower half represents ASCII and the upper half some other 8-bit
69 character set (chosen by setting the font, case tables, syntax
70 tables, etc. appropriately for the character set through ad-hoc
71 means such as the `iso-8859-1' file and the
72 `standard-display-european' function).
73
74 For more info, see `text.c' and the Internals Manual.
75 */
76
50 /* ---------------------------------------------------------------------- */ 77 /* ---------------------------------------------------------------------- */
51 /* Super-basic character properties */ 78 /* Super-basic character properties */
52 /* ---------------------------------------------------------------------- */ 79 /* ---------------------------------------------------------------------- */
53 80
54 /* These properties define the specifics of how our current encoding fits 81 /* These properties define the specifics of how our current encoding fits
161 /* Maximum number of bytes per Emacs character when represented as text, in 188 /* Maximum number of bytes per Emacs character when represented as text, in
162 any format. 189 any format.
163 */ 190 */
164 191
165 #define MAX_ICHAR_LEN 4 192 #define MAX_ICHAR_LEN 4
193
194 #endif /* not MULE */
195
196 #ifdef MULE
197
198 MODULE_API int non_ascii_valid_ichar_p (Ichar ch);
199
200 /* Return whether the given Ichar is valid.
201 */
202
203 DECLARE_INLINE_HEADER (
204 int
205 valid_ichar_p (Ichar ch)
206 )
207 {
208 return (! (ch & ~0xFF)) || non_ascii_valid_ichar_p (ch);
209 }
210
211 #else /* not MULE */
212
213 /* This works when CH is negative, and correctly returns non-zero only when CH
214 is in the range [0, 255], inclusive. */
215 #define valid_ichar_p(ch) (! (ch & ~0xFF))
166 216
167 #endif /* not MULE */ 217 #endif /* not MULE */
168 218
169 /* For more discussion, see text.c, "handling non-default formats" */ 219 /* For more discussion, see text.c, "handling non-default formats" */
170 220