qianxi0410 / qianxi-lang

A dynamic lang interpreter written in golang

qianxi-lang

a lang interpreter written in go

Try

Download

git clone https://github.com/qianxi0410/qianxi-lang

cd qianxi-lang

with REPL

go run main.go

with File Interpreter

go run .\main.go filepath

Documetion

Summery

• C-like syntax
• variable bindings
• numbers and booleans
• a string data structure
• an array data structure
• a hash data structure
• arithmetic expressions
• built-in functions
• first-class and higher-order functions • closures
• logic operator

Keywords

let 、 fn 、 if 、 else 、 elif 、 return 、 true 、 false

Examples

let

let <identifier> = <value>;

let a = 1;
let b = 2.2;
let c = "hello world";
let d = true;

fn

let fibonacci = fn(x) { 
    if (x <= 1) { 
        x
    } else { 
        fibonacci(x - 1) + fibonacci(x - 2);
    } 
};

if

let hello = if (x == 1) {
        "hello world"
    } elif (x == 2) {
       "hello qianxi"
    } else {
       "just hello"
    }

return

let identity = fn(x) {
  return x;
};

identity("qianxi");

operators

1 + 2 + (3.3 * 4) - (10 / 5);
!true;
!false;
+10;
-5;
"Hello" + " " + "World";
1 && 2;
1 || 2;
1 << 2;
2 >> 1;
1 & 2;
1 | 2;
1 ^ 2;
~1;

Built-in Structs

array

let arr = [<expression>, <expression>, ...];

let arr = [1, 2, 3 + 3, fn(x) { x }, add(2, 2), true];

arr[0];
arr[1];

hash

let h = { <expression>: <expression>, <expression>: <expression>, ... };

let hash = {
  "name": "qianxi",
  "age": 21,
  true: "a boolean",
  99: "an integer"
};

hash["name"];
hash["a" + "ge"];
hash[true];
hash[99];
hash[100 - 1];

Built-in Functions

🚀 qianxi lang provide you some built-in functions

len

len(<array | string>): number;

len([1, 2, 3]); // 3
len("hello"); // 5

first

first(<array>): any;

first(["hello", 2, 3]); // "hello"
first([1, 2, 3]); // 1

last

last(<array>): any;

last(["hello", 2, 3]); // 3
last([1, 2, "qianxi"]); // "qianxi"

rest

rest(<array>): array;

rest([]) // NULL
rest([1]) // []
rest([1, 2, 3]) // [2, 3]

push

push(<array>): array
    
push([], 1) // [1]

puts

puts(<any>): NULL
    
puts("hello world") // print : hello world

Licence

MIT