Questions[regex](ubuntu)

I have this file 1.txt:

-e a
b
-e c

d
-e e
f

I want to split it into the following two files.

2.txt

-e a
-e c
-e e

3.txt

b
d
f

where 2.txt contains all the lines starting with -e, and 3.txt contains all the other lines. Extra newlines (such as the extra newline in the middle of the original) can be ignored or kept, and order doesn't matter.

I've tried using split, but it doesn't look like that allows me to use a pattern for splitting (instead a fixed number of lines per split file).

i wrote the following script. It will be used in a build process later. My goal is to decide whether it's a pre release or a release. To archive this i compare $release to a RegEx. If my RegEx matches it's a pre release, if not it's a release.

#/bin/bash
release="1.9.2-alpha1"
echo "$release"
if [[ "$release" =~ \d+\.\d+\.\d+[-]+.* ]];then
echo "Pre"
else
echo "Release"
fi

But as result i always end up with the following:

~$ bash releasescript.sh
1.9.2-alpha1
Release

Version:

Ubuntu 18.04.1 LTS

I used this editor to test my RegEx. I'm stuck for at least 6h, so i would appreciate some help greatly.

I am happy that grep does support Perl Compatible Regular Expressions with the -P option.

Is there a reason why the tool sed does not have this feature?

I've been using GPRename to batch-rename files; this is rather more efficient than individually correcting each file, but still seems to be less efficient than it might be, primarily because either I don't understand the regex syntax used, or because the regex implementation is incomplete1

Given a list of files of the following syntax:

(01) - title of file1.avi
(02) - title of file2.avi
(03) - title of file3.avi

I attempted to use the 'replace' (with the regex option selected, the case-sensitive option deselected):

(\(\d{2}\))

The preview then shows (given that I've specified no 'replace with' option as yet):

title of file1.avi
title of file2.avi
title of file3.avi

Which is great, clearly the regex is identifying the correct group (the (01)). Now, what I was hoping to do (using the JavaScript syntax) in the 'replace with' option is use:

$1

(I also tried using '$1', \1 and '\1')

This was just to check that I could access the matched group, and it seems I can't, the matched group is, as I suppose might be expected, replaced with the literal replacement string.

So, my question: is it possible to match a particular group of characters, in this case the numbers within the brackets, and then insert those into the replacement string? Therefore:

(01) title of file1.avi
(02) title of file2.avi
(03) title of file3.avi

Becomes:

01 title of file1.avi
02 title of file2.avi
03 title of file3.avi

1. I absolutely suspect the former, personally.

I want to find a text editor capable of running and mainly storing regular expressions for later re-use. It should also be able to run them across multiple files.

I know I can get all that with grep, but there is not much for re-use on it. I was able to get some regular expression functionality on Gedit with plugins, but not nearly close to my needs.

There is EditPad Pro for Windows (runs on wine) but native is always better :)