3 CodingStyle - standards while programming for GNU LilyPond
7 Please use these standards while doing programming for GNU LilyPond
9 Functions and methods do not return errorcodes, but use assert for
14 A program should be light and agile, its subroutines
15 connected like a string of pearls. The spirit and intent of
16 the program should be retained throughout. There should be
17 neither too little nor too much, neither needless loops nor
18 useless variables, neither lack of structure nor overwhelming
21 A program should follow the 'Law of Least
22 Astonishment'. What is this law? It is simply that the
23 program should always respond to the user in the way that
26 A program, no matter how complex, should act as a
27 single unit. The program should be directed by the logic
28 within rather than by outward appearances.
30 If the program fails in these requirements, it will be
31 in a state of disorder and confusion. The only way to correct
32 this is to rewrite the program.
34 -- Geoffrey James, "The Tao of Programming"
38 Definitions of classes that are only accessed via pointers
39 (*) or references (&) shall not be included as include files.
44 ".cc" Implementation files
45 ".icc" Inline definition files
46 ".tcc" non inline Template defs
51 (append '(("\\.make$" . makefile-mode)
53 ("\\.icc$" . c++-mode)
54 ("\\.tcc$" . c++-mode)
56 ("\\.pod$" . text-mode)
61 The class Class_name_abbreviation is coded in F<class-name-abbr.*>
69 (add-hook 'c-mode-hook
70 '(lambda ()(setq c-basic-offset 4)))
73 (add-hook 'c++-mode-hook
74 '(lambda() (c-set-style "Stroustrup")
78 If you like using font-lock, you can also add this to your F<.emacs>:
80 (setq font-lock-maximum-decoration t)
81 (setq c++-font-lock-keywords-3
83 c++-font-lock-keywords-3
84 '(("\\b\\([a-zA-Z_]+_\\)\\b" 1 font-lock-variable-name-face)
85 ("\\b\\([A-Z]+[a-z_]+\\)\\b" 1 font-lock-type-face))
88 =head2 CLASSES and TYPES:
91 AClass_name (for Abbreviation_class_name)
96 Type Class::member_type_
98 the C<type> is a Hungarian notation postfix for C<Type>. See below
103 Broken code (hardwired dependencies, hardwired constants, slow
104 algorithms and obvious limitations) should be marked as such:
105 either with a verbose TODO, or with a short "ugh" comment.
109 The source is commented in the DOC++ style. Check out doc++ at
110 http://www.zib.de/Visual/software/doc++/index.html
113 C style comments for multiline comments.
114 They come before the thing to document.
121 Long class documentation.
124 TODO Fix boring_member()
136 short memo. long doco of member()
137 @param description of arguments
140 Rettype member(Argtype);
144 data_member_ = 121; // ugh
150 Unfortunately most of the code isn't really documented that good.
157 ///check that *this satisfies its invariants, abort if not.
160 /// print *this (and substructures) to debugging log
164 protected member. Usually invoked by non-virtual XXXX()
168 /**add some data to *this.
169 Presence of these methods usually imply that it is not feasible to this
174 /// replace some data of *this
177 =head1 HUNGARIAN NOTATION NAMING CONVENTION
179 Proposed is a naming convention derived from the so-called I<Hungarian
184 The Hungarian Notation was conceived by or at least got its name from,
185 the hungarian programmer Charles Simonyi. It is a naming convention
186 with the aim to make code more readable (for fellow programmers), and
187 more accessible for programmers that are new to a project.
189 The essence of the Hungarian Notation is that every identifier has a
190 part which identifies its type (for functions this is the result
191 type). This is particularly useful in object oriented programming,
192 where a particular object implies a specific interface (a set of
193 member functions, perhaps some redefined operators), and for
194 accounting heap allocated memory pointers and links.
198 Another fun quote from Microsoft Secrets:
201 The Hungarian naming convention gives developers the ability
202 to read other people's code relatively easily, with a minmum
203 number of comments in the source code. Jon De Vann estimated
204 that only about 1 percent of all lines in the Excel product
205 code consist of comments, but the code is still very
206 understandable due to the use of Hungarian: "if you look at
207 our source code, you also notice very few comments. Hungarian
208 gives us the ability to go in and read code..."
211 Wow! If you use Hungarian you don't have to document your software!
212 Just think of the hours I have wasted documenting while this "silver bullet"
213 existed. I feel so stupid and ashamed!
221 more keystrokes (disk space!)
225 it looks silly C<get_slu_p()>
229 it looks like code from micro suckers
233 (which) might scare away some (otherwise good?)
234 progammers, or make you a paria in the free
243 not very useful if not used consistently
247 usefullness in I<very large> (but how many classes is very large?)
260 learn about cut and paste / use emacs or vi
261 or lean to type using ten fingers
265 Use emacs dabbrev-expand, with dabbrev-case-fold-search set to nil.
269 use no, or pick less silly, abbrvs.
273 use non-ambiguous postfixes C<identifier_name_type_modifier[_modifier]>
277 Macros, C<enum>s and C<const>s are all uppercase,
278 with the parts of the names separated by underscores.
287 unsigned char. (The postfix _by is ambiguous)
316 Zero terminated c string
324 =head2 User defined types
331 Slur* slur_p = new Slur;
335 The following types modify the meaning of the prefix.
336 These are precede the prefixes:
350 const. Note that the proper order C<Type const> i.s.o. C<const Type>
354 A const pointer. This would be equivalent to C<_c_l>, but since any
355 "const" pointer has to be a link (you can't delete a const pointer),
360 temporary pointer to object (link)
364 pointer to newed object
376 Variable loop: an integer
380 Temporary variable: an unsigned integer
384 Variable test: a character
386 =item C<first_name_str>
388 Variable first_name: a String class object
390 =item C<last_name_ch_a>
392 Variable last_name: a C<char> array
396 Variable foo: an C<Int*> that you must delete
400 Variable bar: an C<Int*> that you must not delete
404 Generally default arguments are taboo, except for nil pointers.
408 For some tasks, some scripts are supplied, notably creating patches, a
409 mirror of the website, generating the header to put over cc and hh
410 files, doing a release.
414 The following generic identifications are used:
421 Intervals are pictured lying on a horizontal numberline (Interval[-1]
422 is the minimum). The 2D plane has +x on the right, +y pointing up.