3 CodingStyle - standards while programming for LilyPond
7 Please use these standards while doing programming for 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 strings 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.
41 Include files in C++ always have the file name extension ".hh".
43 Implementation files in C++ always have the file name
46 Inline definition files always have the file name extension ".icc".
54 (add-hook 'c-mode-hook
55 '(lambda ()(setq c-basic-offset 4)))
58 (add-hook 'c++-mode-hook
59 '(lambda() (c-set-style "Stroustrup")
64 =head2 CLASSES and TYPES:
67 AClass_name (for Abbreviation_class_name)
72 Type Class::member_type_
74 the C<type> is a Hungarian notation postfix for C<Type>. See below
79 The source is commented in the DOC++ style. Check out doc++ at
80 http://www.zib.de/Visual/software/doc++/index.html
83 C style comments for multiline comments.
90 Long class documentation.
103 short memo. long doco of member()
104 @param description of arguments
107 Rettype member(Argtype);
113 Unfortunately most of the code isn't really documented that good.
116 =head2 CLASSNAMES (2)
118 A lot of classes in LilyPond start with 'P', this is to distinguish
119 certain parts of LilyPond: the P stands for Printer, and the P-classes
120 are supposed to be more lowlevel than the others. Example:
122 Staff uses PStaff, PScore and PCol to do the typesetting of
123 symbols. Staff is the "brains" for PStaff
125 NB: in PCursor (which is part of the library) P stands for PointerCursor
132 ///check that *this satisfies its invariants, abort if not.
135 /// print *this (and substructures) to debugging log
139 protected member. Usually invoked by non-virtual XXXX()
143 /**add some data to *this.
144 Presence of these methods usually imply that it is not feasible to this
149 /// replace some data of *this
152 =head1 HUNGARIAN NOTATION NAMING CONVENTION
154 Proposed is a naming convention derived from the so-called I<Hungarian
159 The Hungarian Notation was conceived by or at least got its name from,
160 the hungarian programmer Charles Simonyi. It is a naming convention
161 with the aim to make code more readable (for fellow programmers), and
162 more accessible for programmers that are new to a project.
164 The essence of the Hungarian Notation is that every identifier has a
165 part which identifies its type (for functions this is the result
166 type). This is particularly useful in object oriented programming,
167 where a particular object implies a specific interface (a set of
168 member functions, perhaps some redefined operators), and for
169 accounting heap allocated memory pointers and links.
173 Another fun quote from Microsoft Secrets:
176 The Hungarian naming convention gives developers the ability
177 to read other people's code relatively easily, with a minmum
178 number of comments in the source code. Jon De Vann estimated
179 that only about 1 percent of all lines in the Excel product
180 code consist of comments, but the code is still very
181 understandable due to the use of Hungarian: "if you look at
182 our source code, you also notice very few comments. Hungarian
183 gives us the ability to go in and read code..."
186 Wow! If you use Hungarian you don't have to document your software!
187 Just think of the hours I have wasted documenting while this "silver bullet"
188 existed. I feel so stupid and ashamed!
196 more keystrokes (disk space!)
200 it looks silly C<get_slu_p()>
204 it looks like code from micro suckers
208 (which) might scare away some (otherwise good?)
209 progammers, or make you a paria in the free
218 not very useful if not used consistently
222 usefullness in I<very large>
223 (but how many classes is very large?)
236 learn about cut and paste / use emacs or vi
237 or lean to type using ten fingers
241 Use emacs dabbrev-expand, with dabbrev-case-fold-search set to nil.
245 use no, or pick less silly, abbrvs.
249 use non-ambiguous postfixes C<identifier_name_type_modifier[_modifier]>
252 Macros, C<enum>s and C<const>s are all uppercase,
253 with the parts of the names separated by underscores.
262 unsigned char. (The postfix _by is ambiguous)
291 Zero terminated c string
299 =head2 User defined types
306 Slur* slur_p = new Slur;
310 The following types modify the meaning of the prefix.
311 These are precede the prefixes:
325 const. Note that the proper order C<Type const> i.s.o. C<const Type>
329 A const pointer. This would be equivalent to C<_c_l>, but since any
330 "const" pointer has to be a link (you can't delete a const pointer),
335 temporary pointer to object (link)
339 pointer to newed object
351 Variable loop: an integer
355 Temporary variable: an unsigned integer
359 Variable test: a character
361 =item C<first_name_str>
363 Variable first_name: a String class object
365 =item C<last_name_ch_a>
367 Variable last_name: a C<char> array
371 Variable foo: an C<Int*> that you must delete
375 Variable bar: an C<Int*> that you must not delete