#calculator #terminal

app cork

A command-line calculator for hex-lovers

9 releases

0.2.6 Nov 14, 2022
0.2.5 Nov 14, 2022
0.2.4 Aug 29, 2022
0.2.3 Feb 8, 2022
0.1.2 May 21, 2021

#61 in Math

31 downloads per month


1.5K SLoC


version license Rust


Cork is a simple command-line calculator, mainly targeted towards people who deal with hex numbers. It deals only with integer arithmetic. Expressions may involve mixed bases (limited to decimal, hexadecimal, octal and binary numbers). The global output format may be set to a particular radix - by default it is hex.


Cork is something that I wrote over a weekend, when I was getting annoyed at having to punch in 16 digit hex numbers on my calculator. I wanted something on my screen, and naturally on the terminal. But all the calculator programs that I found online (including a REPL of Python and Octave) had a glaring problem - they could work on hex numbers, but the output was always in decimal. So I hit to cargo new ...


Cork is a rather odd name for a calculator. I wanted something on the lines of kernel calculator, but that's way too long. So kernel became core (technically, that's what it means in English) and calculator, well that can be C. So we have CoreC ... maybe CorC ... ah right, Cork.


Prebuilt binary

For Linux, you can download a pre-built binary here.

For Windows, you can download the portable executable here.

Build from source

If you have cargo installed, then you can build this from source:

git clone https://github.com/RedDocMD/cork
cd cork
cargo build --release

The binary produced will be target/release/cork.

From crates.io

To install from crates.io, run cargo install cork. Then, Cork should be executable with the cork command.


Cork is normally a REPL calculator, so you can put in expressions and it displays the answer. A sample run goes like:

Welcome to cork - a calculator for hex-lovers!
Press Ctrl + D to exit.
cork> 0xCAFE
cork> 0xCAFE + 2 * 8 * 0x20
cork> set of dec
cork> ans
cork> 0xCAFE
Exiting ...

Oh, btw, Cork uses rustyline. So you get the whole readline goodness (including a history).

Cork also features an inline-expression evaluation mode (probably useful in scripts).

In addition, Cork can be run on a file (scripting-mode), which executes the file as a script.


Cork accepts four types of numbers:

  • Decimal: These are regular numbers (10, 23245, 4124, etc).
  • Hexadecimal: These are numbers prefixed by 0x (0xaA 0x5acd, 0x101c, etc).
  • Octal: These are numbers prefixed by 0o (0o12, 0o55315, 0o10034, etc).
  • Binary: These are numbers prefixed by 0b (0b1010, 0b101101011001101, 0b1000000011100, etc).

In addition, ans holds the answer of the last computation. It is initialized to 0 on startup.

Underscores (_) are allowed as separators.

Set directives

Cork has something called set directives, which basically set some global property. They are of the form

set <key> <value>

As of now, Cork has the following keys:

Key Possible Values Purpose
of hex, dec, oct, bin Sets the output format

Temporary format conversion

A number, ans or the result of an expression can be temporary converted to a different output format without change the default one. The 'to' command can have the forms

<number> to <radix>
ans to <radix>
<expression> to <radix>

Supported output formats are:

Possible Formats
hex, dec, oct, bin


cork> 0xCAFE to dec
cork> 0xCAFE + 2 * 8 * 0x20 to bin
cork> ans to hex

Inline evaluation

With the -e/--expr flag, Cork accepts an expression to evaluate. The expression cannot be a set-directive. The expression is evaluated and the answer is printed in the default output radix. The -a/--all-bases flag prints the result in all the four bases.

Script evaluation

With the -f/--file flag, Cork accepts the path of a file. This file will be executed as a script from top to bottom. Any command allowed in the REPL is allowed in the script. The script will print its outputs to stdout and its errors to stderr.


The -p/--punctuate-output flag punctuates the output numbers with underscores. The same can be done with a key of the same name in the config file. The presence of this flag overrides the option set in the config file.


Cork accepts a config file in YAML. In absence of one, default values are assumed.


Cork accepts a path for its config file by the -c/--config option.

Otherwise, Cork looks at the following places for a config file (in the specified order):

  1. $HOME/.cork.yml
  2. $HOME/.cork/cork.yml
  3. $HOME/.config/cork/cork.yml


Key Possible Values Default Purpose
prompt string cork> Prompt to show at the beginning of each line
default_radix Decimal, Hex, Octal, Binary Hex Default radix for the output format
header bool true Show the header at startup
punctuate_output bool false Punctuate output numbers with underscores


Cork is released under GNU General Public License, v2.


~223K SLoC