1 XEMACS CODING STANDARDS
8 Copyright (c) 1996 Ben Wing.
11 This file documents the coding standards used in the XEmacs source
12 code. Note that XEmacs follows the GNU coding standards, which are
13 documented separately in ../man/standards.texi. This file only
14 documents standards that are not included in that document; typically
15 this consists of standards that are specifically relevant to the
18 First, a recap of the GNU standards:
20 -- Put a space after every comma.
21 -- Put a space before the parenthesis that begins a function call,
22 macro call, function declaration or definition, or control
23 statement (if, while, switch, for). (DO NOT do this for macro
24 definitions; this is invalid preprocessor syntax.)
25 -- The brace that begins a control statement (if, while, for, switch,
26 do) or a function definition should go on a line by itself.
27 -- In function definitions, put the return type and all other
28 qualifiers on a line before the function name. Thus, the function
29 name is always at the beginning of a line.
30 -- Indentation level is two spaces. (However, the first and following
31 statements of a while/for/if/etc. block are indented four spaces
32 from the while/for/if keyword. The opening and closing braces are
34 -- Variable and function names should be all lowercase, with underscores
35 separating words, except for a prefixing tag, which may be in
36 uppercase. Do not use the mixed-case convention (e.g.
37 SetVariableToValue ()) and *especially* do not use Microsoft
38 Hungarian notation (char **rgszRedundantTag).
39 -- preprocessor and enum constants should be all uppercase, and should
40 be prefixed with a tag that groups related constants together.
43 Now, the XEmacs coding standards:
45 **** Specially-prefixed functions/variables:
47 -- All global C variables whose value is constant and is a symbol begin
48 with a capital Q, e.g. Qkey_press_event. (The type will always be
50 -- All other global C variables whose value is a Lisp_Object (this
51 includes variables that forward into Lisp variables plus others like
52 Vselected_console) begin with a capital V.
53 -- No C variables whose value is other than a Lisp_Object should begin
54 with a capital V. (This includes C variables that forward into
55 integer or boolean Lisp variables.)
56 -- All global C variables whose value is a struct Lisp_Subr begin with a
57 capital S. (This only occurs in connection with DEFUN ()).
58 -- All C functions that are Lisp primitives begin with a capital F,
59 and no others should begin this way.
61 **** Functions for manipulating Lisp types:
63 -- Any function that creates an empty or mostly empty Lisp object
64 should begin allocate_(). (*Not* make_().) (Except, of course,
65 for Lisp primitives, which usually begin Fmake_()).
66 -- Any function that converts a pointer into an equivalent Lisp_Object
68 -- Any function that converts a Lisp_Object into its equivalent pointer
69 and checks the type and validity of the object (e.g. making sure
70 it's not dead) should begin decode_().
71 -- Any function that looks up a Lisp object (e.g. buffer, face) given
72 a symbol or string should begin get_(). (Except, of course, for
73 Lisp primitives, which usually begin Fget_()).
77 -- Any header-file declarations of the sort
81 go into the "types" section of lisp.h.