Autumn
An easy interpreter to learn.
Features
- Modern C++ style(Based on C++17)
- Support Linux and MacOS
- Full comments
- Support debug in repl
- Higher-order functions supported
- Closure supported
- ...
Quick Start
Install GCC8
- Centos
$ yum install readline-devel.x86_64
$ yum install -y devtoolset-8-toolchain
$ scl enable devtoolset-8 bash- Ubuntu
$ sudo add-apt-repository -y ppa:ubuntu-toolchain-r/test
$ sudo apt-get update -qq
$ sudo apt-get install -qq g++-8
$ apt-get install lib64readline-dev
$ export CXX="g++-8"
$ export CC="gcc-8"
Build & Test
$ make
Repl
- lexer mode
$ ./autumn lexer
- parser mode
$ ./autumn parser
- debug in parser mode
$ DEBUG_AUTUMN=1 ./autumn parser
- eval mode
$ ./autumn eval
Demo
An example below showing how to write quick sort.
- You need a filter function
let filter = fn(arr, f) {
let iter = fn(arr, accumulated) {
if (len(arr) == 0) {
accumulated
} else {
let e = if (f(first(arr))) {
push(accumulated, first(arr));
} else {
accumulated
}
iter(rest(arr), e);
}
};
iter(arr, []);
};- QuickSort
let quickSort = fn(arr) {
if (len(arr) == 0) {
return arr;
} else {
let head = first(arr);
let smaller = filter(rest(arr), fn(x) { x <= head });
let bigger = filter(rest(arr), fn(x) { x > head });
return quickSort(smaller) + [head] + quickSort(bigger);
}
}let a = [4,5,3,4,6,6]
quickSort(a)
Contributor
Allen.
License
This project maintained under BSD 2.
Contact
QQ Group for Autumn: 985682510 QQ Group for Linuxers: 610441700