Re: [PATCH] Avoid unportable nested double- and backquotes in shell scripts.

From: Jonathan Nieder <jrnieder@gmail.com>
Date: Jan 8, 2011, 18:22 UTC
Message-ID: <20110108182201.GB29788@burratino>
In-Reply-To: <20110108164825.GC28898@burratino>

Jonathan Nieder wrote:

Show 10 quoted lines

> From a quick grep, it seems you are right:
> 
>  $ git grep -c -F -e '`' -- 't/*.sh' | cut -d: -f2 | sum
>  65126     1
>  $ git grep -c -F -e '$(' -- 't/*.sh' | cut -d: -f2 | sum
>  64807     1
>  $ git grep -c -F -e '`' -- '*.sh' | cut -d: -f2 | sum
>  13350     1
>  $ git grep -c -F -e '$(' -- '*.sh' | cut -d: -f2 | sum
>  07810     1

sum does something totally different than I expected. With [1] comes the more reasonable

 $ git grep -c -F -e '`' -- 't/*.sh' | cut -d: -f2 | addup
 485
 $ git grep -c -F -e '$(' -- 't/*.sh' | cut -d: -f2 | addup
 2620
 $ git grep -c -F -e '`' -- '*.sh' | cut -d: -f2 | addup
 594
 $ git grep -c -F -e '$(' -- '*.sh' | cut -d: -f2 | addup
 3133

So the code bloat and use of backticks are less dire than I feared.

[1] 
	addup () {
		sum=0
		while read term
		do
			: $((sum = $sum + $term))
		done
		echo $sum
	}