in notepad++ replace convert comma separated spaces with regular expression

Question

I have comma separated tokens, I need to convert them to tokens in colons separated by spaces. I wanted to use regular expression in notepad++ but had a problem.

My input is:

aaaaa, bbb ,cccc, hhhh, fff,t

I would like to get as result:

aaaaa     bbb       cccc     hhhh      fff       t

Each token gets exactly 10 characters

My problem is how to make the output exactly 10 characters?

Answer 1

Description

I see this as a two step process. Step One replace all the commas with 10 spaces. Step Two capture 10 characters and all trailing spaces, and replace with just the 10 captured characters.

---

Step One - Replace commas with 10 spaces

,\s*|\s*$

Replace with: __________ these are unbars, but you should really use ten or more spaces.

Live Demo: https://regex101.com/r/mR1eS9/1

Sample Text

aaaaa, bbb ,cccc, hhhh, fff,t

After Replacement

aaaaa          bbb           cccc          hhhh          fff          t                    
123456789,123456789,123456789,123456789,123456789,123456789,123456789,123456789

_{Note: I inserted the number line here to help illustrate the number and position of characters}

---

Step Two - Capture 10 characters and all trailing spaces

(.{10})[^\S\n\r]*

Replace with: $1

Live Demo: https://regex101.com/r/uL8oO7/2

Sample Text

Because this is step two, the sample text is the output from step one above

aaaaa          bbb           cccc          hhhh          fff          t                    

After Replacement

aaaaa     bbb       cccc      hhhh      fff       t         
123456789,123456789,123456789,123456789,123456789,123456789,123456789,123456789

_{Note: I inserted the number line here to help illustrate the number and position of characters}

Answer 2

Regex computation model is so simple that it cannot count. However, in situations when you have only nine possible non-empty matches you can run nine separate global replacements to cover all possibilities (underscores _ are used in place of spaces for clarity):

Search         Replacement
-------------  -----------
(?<=\b\S{9}),\s  _
(?<=\b\S{8}),\s  __
(?<=\b\S{7}),\s  ___
(?<=\b\S{6}),\s  ____
...
(?<=\b\S{1}),\s  _________

Each replacement operation matches a comma, space pair that follows x non-space characters, and replaces them with 10-x spaces.

Answer 3

Perhaps a solution with a programming language might be better to read and comprehend.
Find code samples for PHP and Python below (can easily be adopted to other languages as well):

PHP

<?php
$string = "aaaaa, bbb ,cccc, hhhh, fff,t";
$regex = '~(\w+)(\s*,|$)~';
# look for word characters, followed by spaces (or not) 
# and a comma or the end of the string

$string = preg_replace_callback(
    $regex,
    function($match) {
        return str_pad($match[1], 10);
    },
    $string);
echo $string;
# aaaaa      bbb       cccc       hhhh       fff       t         
?>

See a demo on ideone.com.

---

Python

import re

string = "aaaaa, bbb ,cccc, hhhh, fff,t";

def repl(match):
    return match.group(1).ljust(10)

rx = r'(\w+)(\s*,|$)'
string = re.sub(rx, repl, string)
print string

A demo on ideone.com as well.