仅删除 bash 中字符串中每个逗号后出现的那些空格

Question

I am new in bash and would like to know best way to remove those white spaces which are available after each comma in string. For eg I have following input string :

abc, xyz,  cdf axy bnz cnm

Resultant string should be :

abc,xyz,cdf axy bnz cnm

Answer 1

You can use sed for this

$ sed -E 's/, +/,/g' input_file
abc,xyz,cdf axy bnz cnm

Answer 2

Turn on the extglob option and do it with parameter expansion pattern replacement:

#!/usr/bin/env bash

str="abc, xyz,  cdf axy bnz cnm"
shopt -s extglob
printf "%s\n" "${str//,+([[:space:]])/,}"