Debian Live マニュアル　日本語版

10　コーディングスタイル

This chapter documents the coding style used in live-helper and
(ideally) in live-initramfs.

10.1. Compatibility

* Don't use syntax or semantics that are unique to the Bash shell. For example, the use of array constructs. * Only use the POSIX subset - for example, use $(foo) over `foo`. * You can check your scripts with 'sh -n' and 'checkbashisms'

10.2. Indenting

* Always use tabs over spaces.

10.3. Wrapping

* Generally, lines are 80 chars at maximum. * Use the "Linux style" of line breaks:

Bad:

if foo; then bar fi

Good:

if foo then bar fi

* The same holds for functions:

Bad:

foo () { bar }

Good:

foo () { bar }

10.4. Variables

* Variables are always in capital letters. * Variables that used in config always start with LH_ prefix. * Internal temporary variables should start with the _LH_ prefix. * Local variables start with __LH_ prefix. * Use braces around variables; eg. write ${FOO} instead of $FOO. * Always protect variables with respect to potential whitespaces, write "${FOO}" not ${FOO}. * For consistency reasons, always use quotes when assigning values to variables:

Bad:

FOO=bar

Good:

FOO="bar"

* If multiple variables are used, quote the full expression:

Bad:

if [ -f "${FOO}"/foo/"${BAR}"/bar ] then foobar fi

Good:

if [ -f "${FOO}/foo/${BAR}/bar" ] then foobar fi

10.5. Miscellaneous

* Use "|" (without the surround quotes) as a seperator in calls to sed, e.g. "sed -e 's|foo|bar|'" (without ""). * Don't use the test command for comparisons or tests, use "[" "]" (without ""), e.g. "if [ -x /bin/foo ]; ..." and not "if test -x /bin/foo; ...".