 _     _   
 ___ ___ ___ ___|_|___| |_ 
| . |_ -|  _|  _| | . |  _|
|_  |___|___|_| |_|  _|_|  
|___|             |_|

</div><br>

Introduction

This is a statically and strongly typed language written in Go, the syntax of Java and Go is referenced.

Target

Provides the ability to write Go language in script form, retains the advantages of Go language (goroutine, etc.), and adds more syntactic sugar for ease of use.

The current Alpha version is for study and experimentation only.

hello_world.gs:

println("hello world");

❯ gscript hello_world.gs
hello world

Playground

Online address: https://gscript.crossoverjie.top/

Source code:https://github.com/crossoverJie/gscript-homepage

Features

[x] Class declaration
[x] Function declaration and call
[x] Primitive type: int/string/float/bool/byte
[x] Array type
[x] nil type
[x] any type
[x] Function type
[x] Closure：Functions as First-Class Objects
[x] Native function
[x] Standard library
- [x] Map
[x] Variable arguments
[x] Operator overloading
[x] Native support json
[x] Native support http
[x] Example
- [x] LeetCode
  - [x] LeetCode: Linked list cycle
  - [x] LeetCode: Two sum
- [x] Print fibonacci
- [x] Print YangHui triangle
- [x] HTTP Service
[ ] PKG manager
[ ] Unit Test command line

Demo

Hello world

println("hello world");

Print fibonacci

func int() fib(){
    int a = 0;
    int b = 1;
    int fibonacci(){
        int c = a;
        a = b;
        b = a+c;
        return c;
    }
    return fibonacci;
}

func int() f = fib();

for (int i = 0; i < 10; i++){
    println(f());
}

Webapp

This is a dynamic web application written in GScript.

https://gscript.crossoverjie.top/api/index

Source code： https://github.com/crossoverjie/gscript-homepage

YangHui triangle

int num(int x,int y){
	if (y==1 || y ==x) {
		return 1;
	}
    int v1 = num(x - 1, y - 1);
    int v2 = num(x - 1, y);
	int c = v1+v2;
    // int c = num(x - 1, y - 1)+num(x - 1, y);
	return c;
}

printTriangle(int row){
	for (int i = 1; i <= row; i++) {
        for (int j = 1; j <= row - i; j++) {
           print(" ");
        }
        for (int j = 1; j <= i; j++) {
            print(num(i, j) + " ");
        }
        println("");
    }
}

printTriangle(7);

// output:
      1 
     1 1 
    1 2 1 
   1 3 3 1 
  1 4 6 4 1 
 1 5 10 10 5 1 
1 6 15 20 15 6 1

More examples:https://github.com/crossoverJie/gscript/tree/main/example

Install

Binary

Download the latest binaries here

🐳Docker

docker pull crossoverjie/gscript

REPL

docker run --rm -it  crossoverjie/gscript:latest gscript

Run script

docker run --rm -v $PWD:/usr/src/gscript -w /usr/src/gscript crossoverjie/gscript gscript {yourpath}/temp.gs

Build from Source Code

git clone https://github.com/crossoverJie/gscript.git
cd gscript
make build-code
./gscript

REPL

> ./gscript

Syntax

Primitive

The current version supports four primitive type: int/string/float/bool and nil type.

Variable declaration syntax: type identifier (= expr)?.

int a=10;
string b,c;
float e = 10.1;
bool f = false;
byte by = 1;
string x = ^
{
    "name": "bob",
    "age": 20,
    "skill": {
        "lang": [
            {
                "go": {
                    "feature": [
                        "goroutine",
                        true
                    ]
                }
            }
        ]
    }
}^

Array

Array declaration syntax: ('[' DECIMAL_LITERAL ']')? '{' (variableInitializer (',' variableInitializer)* (',')? )? '}'

// Declare and initialize
int[] a={1,2,3};
println(a);

// Declare an empty array and specify the length
int[] table = [4]{};

println("");
// Append data to array.
append(a,4);
println(a);
for(int i=0;i<len(a);i++){
	println(a[i]);
}

// Access to data by index.
int b=a[2];
println(b);

// byte array
string s = "10";
byte[] a= toByteArray(s);
printf("a=%v ",a);
string s1 = toString(a);
printf("s1=%s",s1);
assertEqual(s1,s);

// slice an array into a new array.
int[] a = {1,2,3};
int s=1;
int[] b = a[s:len(a)];
println(b);
// output: [2 3]

any type

An any type may hold values of all type.

any a =10;
println(a);

int fun1(any a,int b){
	return a+b;
}
int v =fun1(1,2);
println(v);
assertEqual(v,3);

any v2 = fun1(1,2);
println(v2);
assertEqual(v2,3);

int fun2(int a, any b){
	return a+b;
}
int v3 =fun2(1,2);
println(v3);
assertEqual(v3,3);

int fun3(any a, any b){
	return a+b;
}
int v4 =fun3(1,2);
println(v4);
assertEqual(v4,3);

int fun4(any a, any b){
	return a+b;
}
string v5 =fun4("10", "20");
println(v5);
assertEqual(v5,"1020");

Example: Standard library

Class

class ListNode{
    int value;
    ListNode next;
    ListNode(int v, ListNode n){
        value =v;
        next = n;
    }
}

// The new keyword is not required to call the constructor.
ListNode l1 = ListNode(1, nil);

// Using . to access object property or method.
println(l1.value);

The default comes with a parameterless constructor

class Person{
	int age=10;
	string name="abc";
	int getAge(){
		return 100+age;
	}
}

// parameterless constructor
Person xx= Person();
println(xx.age);
assertEqual(xx.age, 10);
println(xx.getAge());
assertEqual(xx.getAge(), 110);

function

// cycle linked list
bool hasCycle(ListNode head){
    if (head == nil){
        return false;
    }
    if (head.next == nil){
        return false;
    }

    ListNode fast = head.next;
    ListNode slow = head;
    bool ret = false;
    for (fast.next != nil){
        if (fast.next == nil){
            return false;
        }
        if (fast.next.next == nil){
            return false;
        }
        if (slow.next == nil){
            return false;
        }
        if (fast == slow){
            ret = true;
            return true;
        }

        fast = fast.next.next;
        slow = slow.next;
    }
    return ret;
}

ListNode l1 = ListNode(1, nil);
bool b1 =hasCycle(l1);
println(b1);
assertEqual(b1, false);

ListNode l4 = ListNode(4, nil);
ListNode l3 = ListNode(3, l4);
ListNode l2 = ListNode(2, l3);
bool b2 = hasCycle(l2);
println(b2);
assertEqual(b2, false);

l4.next = l2;
bool b3 = hasCycle(l2);
println(b3);
assertEqual(b3, true);

Function declaration syntax: typeTypeOrVoid? IDENTIFIER formalParameters ('[' ']')*

add(int a){}

When there is no return value, the return type can also be ignored.

Closure

Function type syntax: func typeTypeOrVoid '(' typeList? ')'

// External variable, global shared.
int varExternal =10;
func int(int) f1(){
	// Closure variable.
	int varInner = 20;
	int innerFun(int a){
		println(a);
		int c=100;
		varExternal++;
		varInner++;
		return varInner;
	}
	return innerFun;
}

// f2 is a function type, the return type and parameter are both int.
func int(int) f2 = f1();
for(int i=0;i<2;i++){
	println("varInner=" + f2(i) + ", varExternal=" + varExternal);
}
println("=======");
func int(int) f3 = f1();
for(int i=0;i<2;i++){
	println("varInner=" + f3(i) + ", varExternal=" + varExternal);
}

Output:

0
varInner=21, varExternal=11
1
varInner=22, varExternal=12
=======
0
varInner=21, varExternal=13
1
varInner=22, varExternal=14

Variable arguments

GScript also support variable arguments：

int add(string s, int ...num){
	println(s);
	int sum = 0;
	for(int i=0;i<len(num);i++){
		int v = num[i];
		sum = sum+v;
	}
	return sum;
}
int x = add("abc", 1,2,3,4);
println(x);
assertEqual(x, 10);

Operator overloading

Operator that Gscript support:

+-*/
== != < <= > >=

Overloading function must be operator, and append operator.

class Person{
	int age;
	Person(int a){
		age = a;
	}
}
Person operator + (Person p1, Person p2){
	Person pp = Person(p1.age+p2.age);
	return pp;
}
Person operator - (Person p1, Person p2){
	Person pp = Person(p1.age-p2.age);
	return pp;
}
Person operator * (Person p1, Person p2){
	Person pp = Person(p1.age * p2.age);
	return pp;
}
Person operator / (Person p1, Person p2){
	Person pp = Person(p1.age / p2.age);
	return pp;
}
bool operator == (Person p1, Person p2){
	return p1.age==p2.age;
}
bool operator != (Person p1, Person p2){
	return p1.age!=p2.age;
}
bool operator > (Person p1, Person p2){
	return p1.age>p2.age;
}
bool operator >= (Person p1, Person p2){
	return p1.age>=p2.age;
}
bool operator < (Person p1, Person p2){
	return p1.age<p2.age;
}
bool operator <= (Person p1, Person p2){
	return p1.age<=p2.age;
}
Person p1 = Person(10);
Person p2 = Person(20);
//Person p3 =  operator(p1,p2);
Person p3 = p1+p2;
println("p3.ag

Gscript

Install / Use

README

Introduction

Target

Playground

Features

Demo

Hello world

Print fibonacci

Webapp

YangHui triangle

Install

Binary

🐳Docker

REPL

Run script

Build from Source Code

REPL

Syntax

Primitive

Array

any type

Class

function

Closure

Variable arguments

Operator overloading