cutr

This software is just a reimplementation of the popular Linux cut command provided by the core-utils package, with support for regular expressions.

Problem

By default, cut allows the user to specify a single character as a delimiter; this limitation could lead to write more complex bash scripts when dealing with formatted output or non-single-character-delimited output.

Here's an example of a formatted output processed with cut, when processing input like

field1:  value
field10: value 

cut alone cannot extract just the value column

echo -n "field1:  value1\nfield10: value2\n" | cut -d' ' -f 2

Which results in output

value2

While the correct output would be retrieved with something like

echo -n "field1:  value1\nfield10: value2\n" | rev | cut -d' ' -f1 | rev
echo -n "field1:  value1\nfield10: value2\n" | tr -s ' ' | cut -d' ' -f2
# ...and so on

But when the separator is not a single space, and with each tool following its own pattern syntax, these solution become harder to read and to mantain

Solution

cutr on the other hand, allows the user to provide a regular expression as a delimiter, leveraging the C++ built-in regex engine and the well known and documented ECMAScript syntax

Hence the same script could become

echo -n "field1:  value1\nfield10: value2\n" | cutr -d"\\s+" -f2

And the output would be the expected one

Installation

The only dependency is the g++ compiler which come preinstalled in many Linux distros.

The following instructions will install this tool in your /usr/bin/ folder, feel free to edit the destination path accordingly if this is not what you want

git clone https://github.com/luco5826/cutr.git
cd cutr
g++ cutr.cpp -O2 -o cutr

And, if you want it installed in your default executable folder, simply copy it inside /usr/bin

sudo cp cutr /usr/bin

Disclaimer

Some notes on the usage of cutr instead of cut:

• cutr is not a drop-in replacement for the original cut command, since it lacks some other features that will definitely be implemented in the future also in cutr, but for basic scripting it may be a more flexible choice indeed.
• when dealing with ranges (e.g., fields 2-4), the original cut includes in the output also the delimiter. cutr outputs instead just the selected fields (in this case 2, 3, 4) without the original delimiter