From bc979945305b87caf1e5975d30d42bafd88ad846 Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Wed, 13 Oct 2010 11:15:14 -0700 Subject: [PATCH] CodingGuidelines: reword parameter expansion section Group entries related to parameter substitutions together and avoid using the word "regexp" to refer to the ${parameter/pattern/string} substitution (banned), as the pattern there is a shell glob and not a regular expression. Signed-off-by: Junio C Hamano --- Documentation/CodingGuidelines | 27 +++++++++++++++------------ 1 file changed, 15 insertions(+), 12 deletions(-) diff --git a/Documentation/CodingGuidelines b/Documentation/CodingGuidelines index 8346c1972..09ffc4656 100644 --- a/Documentation/CodingGuidelines +++ b/Documentation/CodingGuidelines @@ -35,25 +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. - - 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). + - 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}. - - No regexp ${parameter/pattern/string}. + - We use Arithmetic Expansion $(( ... )). + + - 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). -- 2.30.2