HuwInterpreter

HuwInterpreter is a hand written interpreter designed to parse and execute HuwCode script.

HuwInterpreter is an interpreter built in C++ for a custom language I developed named HuwCode. The project was built out of self-interest and understanding on how interpreters work and written. The language supports 70+ built in functions, custom user defined functions, scopes (each function has a scope), variables with types of double (number), string (text) and associated array.

User documentation can be found here.

WASM version can be found here (https://huwdp.co.uk/huwcode-wasm/output.html). Press Cancel button to see result after executing code.

Code Example

function fac(n)
{
    return facRec(1, n);
}

function facRec(acc, n)
{
    if (n < 2)
    {
        return acc;
    }
    return facRec(n * acc, n - 1);
}
print(fac(14));

Dependencies

• libcurl4-openssl-dev
• libcurl4
• libreadline
• libreadline-dev

Installation

Building

sudo apt-get install git g++ cmake make libcurl5-openssl-dev curl pkg-config
sudo apt-get install lib32readline8 lib32readline-dev libreadline-dev
git clone https://github.com/huwdp/huwinterpreter.git
cd huwinterpreter/source
./build.sh

Files will be put in source/build location.

Install

Copy binary into sbin folder. Binary is in build directory.

sudo cp ./HuwInterpreter /usr/sbin/huw

Build App-Image

sudo apt-get install wget
cd huwinterpreter/build-appimage/
wget https://github.com/probonopd/linuxdeployqt/releases/download/continuous/linuxdeployqt-continuous-x86_64.AppImage
chmod a-x linuxdeployqt-continuous-x86_64.AppImage
chmod 777 linuxdeployqt-continuous-x86_64.AppImage
./build-app-image.sh

Usage example

1. Usage: [filename] to run file.
2. Usage: -t [text] to run text.
3. Usage: --hc for HuwCode formatter
4. Usage: -h for help.

For more examples and usage, please refer to the user documentation here.

Releases

Binaries can be downloaded here (https://github.com/huwdp/huwinterpreter/releases).

Windows build available although some functionality is disabled. List of things disabled in Windows build:

• Readline user input
• sleep
• weekday
• weekdayName
• year
• monthName
• random
• month
• currentTime
• clock
• regexSearch
• regexReplace
• regexMatch
• timeFormat
• httpGet
• httpPost
• httpPut
• httpDelete
• now

Meta

Huw Pritchard – @huwdp – huwdp.co.uk GNU GENERAL PUBLIC LICENSE Version 3 (GPL 3).. See license.txt for more information.

Contributing

1. Fork it here
2. Create your branch (git checkout -b xxx)
3. Commit your changes (git commit -am 'Comment')
4. Push branch (git push origin xxx)
5. Create a new pull request

Personal notes

The project should have been structured different. This project started while the famous Crafting interpreters book was in-progress so I had took no guidance on how the system architecture should look like. This project should have used a single Cpp file for interpreting the AST rather than have the logic inside each of the nodes. This change would allow me to add Classes to the system due to the dependency hell I got myself into. Overall I’m happy with HuwCode so I’ll leave it as it is.