X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=Documentation%2FCodingGuidelines;h=09ffc46563cba1057b37ba4a5701858fb95c5dda;hb=7e4eb210bdf2a612d8bf4cc106d99ba190f73e3e;hp=b8bf618a30fd32a014e41e1ba9914f5e652bdefd;hpb=3a2dd481e51ed3ea01b84c7db4c661a0a3d5279c;p=git.git

diff --git a/Documentation/CodingGuidelines b/Documentation/CodingGuidelines
index b8bf618a3..09ffc4656 100644
--- a/Documentation/CodingGuidelines
+++ b/Documentation/CodingGuidelines
@@ -35,21 +35,28 @@ For shell scripts specifically (not exhaustive):
    properly nests.  It should have been the way Bourne spelled
    it from day one, but unfortunately isn't.
 
- - We use ${parameter-word} and its [-=?+] siblings, and their
-   colon'ed "unset or null" form.
+ - We use POSIX compliant parameter substitutions and avoid bashisms;
+   namely:
 
- - We use ${parameter#word} and its [#%] siblings, and their
-   doubled "longest matching" form.
+   - We use ${parameter-word} and its [-=?+] siblings, and their
+     colon'ed "unset or null" form.
 
- - We use Arithmetic Expansion $(( ... )).
+   - We use ${parameter#word} and its [#%] siblings, and their
+     doubled "longest matching" form.
+
+   - No "Substring Expansion" ${parameter:offset:length}.
 
- - No "Substring Expansion" ${parameter:offset:length}.
+   - No shell arrays.
 
- - No shell arrays.
+   - No strlen ${#parameter}.
 
- - No strlen ${#parameter}.
+   - No pattern replacement ${parameter/pattern/string}.
+
+ - We use Arithmetic Expansion $(( ... )).
 
- - No regexp ${parameter/pattern/string}.
+ - Inside Arithmetic Expansion, spell shell variables with $ in front
+   of them, as some shells do not grok $((x)) while accepting $(($x))
+   just fine (e.g. dash older than 0.5.4).
 
  - We do not use Process Substitution <(list) or >(list).