bash array into string pattern-CodePudding

How do I change a bash array into a string with this pattern? Let's say I have arr=(a b c d) and I want to change to this pattern 'a' 'b' 'c' 'd' with the white space in between.

PS-I figured out this pattern 'a' 'b' 'c' 'd' but not sure how to put " " instead of just " " in between.

CodePudding user response：

Like this:

#!/bin/bash

arr=(a b c d)
str="${arr[@]}"
str=${str// /   } # Parameter Expansion
sed "s/[a-z]/'&'/g" <<< "$str"

Output

'a'   'b'   'c'   'd'

Check

See: http://mywiki.wooledge.org/BashFAQ/073 and "Parameter Expansion" in man bash. Also see http://wiki.bash-hackers.org/syntax/pe.

CodePudding user response：

I would do it like so:

$ str=$(printf "'%s'   " "${arr[@]}")
$ str=${str%   }
$
$ echo "$str"
'a'   'b'   'c'   'd'