84 lines
2.7 KiB
Plaintext
Executable File
84 lines
2.7 KiB
Plaintext
Executable File
UltraDefrag Coding Style
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1. Whitespace
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Of course, the most important aspect in any coding style is whitespace.
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UltraDefrag indents are four spaces. Tabs are never used, except of files
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copied entirely from external sources (like Lua, getopt and others).
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Spaces of course are superior to tabs because:
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- You have just one way to specify whitespace, not two. Ambiguity breeds
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mistakes.
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- The confusion surrounding 'use tabs to indent, spaces to justify' is gone.
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- Tab indents push your code to the right, making your screen seriously
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unbalanced.
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- Tabs will be rendered incorrectly on editors who are misconfigured not
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to use tab stops of eight positions.
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- Tabs are rendered badly in patches, causing off-by-one errors in almost
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every line.
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- It is the UltraDefrag coding style.
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Do not leave whitespace dangling off the ends of lines.
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2. Line width
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Lines are 80 characters; not longer whenever possible.
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Rationale:
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- Some people like to tile their 24" screens with a 6x4 matrix of 80x24
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xterms and use vi in all of them. The best way to punish them is to
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let them keep doing it.
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- Code and especially patches is much more readable if limited to a sane
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line length. Eighty is traditional.
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- It is the UltraDefrag coding style.
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3. Naming
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Variables are lower_case_with_underscores; easy to type and read.
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4. Block structure
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Every multiline indented statement is braced. The opening brace is on the
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line that contains the control flow statement that introduces the new block;
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the closing brace is on the same line as the else keyword, or on a line
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by itself if there is no else keyword. Example:
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if(a == 5){
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printf("a was 5.\n");
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do_something();
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} else if(a == 6){
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printf("a was 6.\n");
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} else {
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printf("a was something else entirely.\n");
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}
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Note that 'else if' is considered a single statement; otherwise a long if/
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else if/else if/.../else sequence would need an indent for every else
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statement.
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Note that if the first statement is braced, all its counterparts should
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be enclosed by braces too regardless of whether they are single-line or not
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(as in else statement in example above).
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An exception is the opening brace for a function; for reasons of tradition
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and clarity it comes on a line by itself:
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void a_function(void)
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{
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do_something();
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}
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Rationale: a consistent (except for functions...) bracing style reduces
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ambiguity and avoids needless churn when lines are added or removed.
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Furthermore, it is the UltraDefrag coding style.
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5. The main rule (post scriptum)
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Keep style of sources consistent, it helps make the code more readable!
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===================================
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Adopted from the QEMU Coding Style
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Dmitri Arkhangelski, 12 Nov 2011
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