interface translatable. See "Marking strings for translation" in
po/README.
+ - We do not write our "test" command with "-a" and "-o" and use "&&"
+ or "||" to concatenate multiple "test" commands instead, because
+ the use of "-a/-o" is often error-prone. E.g.
+
+ test -n "$x" -a "$a" = "$b"
+
+ is buggy and breaks when $x is "=", but
+
+ test -n "$x" && test "$a" = "$b"
+
+ does not have such a problem.
+
+
For C programs:
- We use tabs to indent, and interpret tabs as taking up to
- Double negation is often harder to understand than no negation
at all.
+ - There are two schools of thought when it comes to comparison,
+ especially inside a loop. Some people prefer to have the less stable
+ value on the left hand side and the more stable value on the right hand
+ side, e.g. if you have a loop that counts variable i down to the
+ lower bound,
+
+ while (i > lower_bound) {
+ do something;
+ i--;
+ }
+
+ Other people prefer to have the textual order of values match the
+ actual order of values in their comparison, so that they can
+ mentally draw a number line from left to right and place these
+ values in order, i.e.
+
+ while (lower_bound < i) {
+ do something;
+ i--;
+ }
+
+ Both are valid, and we use both. However, the more "stable" the
+ stable side becomes, the more we tend to prefer the former
+ (comparison with a constant, "i > 0", is an extreme example).
+ Just do not mix styles in the same part of the code and mimic
+ existing styles in the neighbourhood.
+
+ - There are two schools of thought when it comes to splitting a long
+ logical line into multiple lines. Some people push the second and
+ subsequent lines far enough to the right with tabs and align them:
+
+ if (the_beginning_of_a_very_long_expression_that_has_to ||
+ span_more_than_a_single_line_of ||
+ the_source_text) {
+ ...
+
+ while other people prefer to align the second and the subsequent
+ lines with the column immediately inside the opening parenthesis,
+ with tabs and spaces, following our "tabstop is always a multiple
+ of 8" convention:
+
+ if (the_beginning_of_a_very_long_expression_that_has_to ||
+ span_more_than_a_single_line_of ||
+ the_source_text) {
+ ...
+
+ Both are valid, and we use both. Again, just do not mix styles in
+ the same part of the code and mimic existing styles in the
+ neighbourhood.
+
+ - When splitting a long logical line, some people change line before
+ a binary operator, so that the result looks like a parse tree when
+ you turn your head 90-degrees counterclockwise:
+
+ if (the_beginning_of_a_very_long_expression_that_has_to
+ || span_more_than_a_single_line_of_the_source_text) {
+
+ while other people prefer to leave the operator at the end of the
+ line:
+
+ if (the_beginning_of_a_very_long_expression_that_has_to ||
+ span_more_than_a_single_line_of_the_source_text) {
+
+ Both are valid, but we tend to use the latter more, unless the
+ expression gets fairly complex, in which case the former tends to
+ be easier to read. Again, just do not mix styles in the same part
+ of the code and mimic existing styles in the neighbourhood.
+
+ - When splitting a long logical line, with everything else being
+ equal, it is preferable to split after the operator at higher
+ level in the parse tree. That is, this is more preferable:
+
+ if (a_very_long_variable * that_is_used_in +
+ a_very_long_expression) {
+ ...
+
+ than
+
+ if (a_very_long_variable *
+ that_is_used_in + a_very_long_expression) {
+ ...
+
- Some clever tricks, like using the !! operator with arithmetic
constructs, can be extremely confusing to others. Avoid them,
unless there is a compelling reason to use them.