🍈 Mellang 🍈

Mellang, an interpreted programming language

Mellang VSCode Extension

You can download it on https://marketplace.visualstudio.com/items?itemName=Mello.mellang

Mellang can do almost anything that a basic programming language does:

Types

Mellang has the following data types: null, bool, int, str, array, hash,fn and a "strange" float

Type	Syntax
null	`null`
bool	`true false`
int	`0 24 1654 -10`
str	`"blablabla string here"`
array	`[] [1, 2] [1, 2, 3]`
hash	`{} {"a": 1} {"a": 1, "b": 2}`
float	`1.6 1.6324 215.16`

Variable Bindings

You can use 'moonvar (var) = (expression)' or just '(var) <- (expression)'

moonvar myVar = 5
anotherVar <- 5

Arithmetic Expressions

>> myVar <- 10
>> moonvar anotherVar <- myVar * 2
>> (myVar + anotherVar) / 2 - 3
12

OwO Operators

moonvar funcOne = fn(x){x *10}

moonvar TEST = fn(x){x * 2}

moonvar ac = OwO 10 ~> funcOne ~> TEST ~> funcOne ~> funcOne ~> funcOne
(10 * 10 * 2 * 10 * 10 * 10)

>> ac
> 200000

moonvar myList = [1,2,3,4,5]

moonvar sumList = fn(list){map(list, TestTWO)}

OwO myList ~> sumList ~> sumList;
>[5,6,7,8,9]

moonvar elixirLike = OwO "Eae Beleza" ~> String_Upcase ~> String_Split;
>[EAE, BELEZA?]

Conditional Expressions

Mellang supports if and else:

>> a <- 10
>> b <- a * 2
>> c <- if (b > a) { 99 } else { 100 }
>> c
> 99

>> a <- 10
>> b <- 10
>> c <- if (b >= a) { 99 } else { 100 }
>> c
> 99

Installation

TODO

Usage example

Variable Declaration

moonvar myVariable = 5
moonvar myFunction = fn(x){x + 1}
moonvar myHash = {"name": "myName", "otherName : "randomName"}
moonvar myList = [1,3,4,5, fn(x){x + 1}]

myList[4](5)
> 6

myHash["name"]
>myName

map([1,2,3,4],fn(x){x * 2})
>[2,4,6,8]

sum(map([1,2,3,4],fn(x){x * 2}))
>20

While Loops

Mellang supports only one looping construct, the while loop:

x <- 3
myList <- [1,2,3,4,5]

while (x > 0) {
 myList <- map(myList,fn(x){x * 2}) 
 plsShow(myList) 
 x <- x - 1
}

// [2,4,6,8,10]
// [4,8,12,16,20]
// [8,16,24,32,40]

Functions and Closures

You can define named or anonymous functions, including functions inside functions that reference outer variables (closures).

>> moonvar multiply = fn(x, y) { x * y }
>> multiply(50 / 2, 1 * 2)
50
>> fn(x) { x + 10 }(10)
20
>> moonvar newAdder = fn(x) { fn(y) { x + y } }
>> moonvar addTwo = newAdder(2)
>> addTwo(3)
5
>> moonvar sub = fn(a, b) { a - b }
>> moonvar applyFunc = fn(a, b, func) { func(a, b) }
>> applyFunc(10, 2, sub)
8

Recursive Functions

Monkey also supports recursive functions including recursive functions defined in the scope of another function (self-recursion).

>> moonvar wrapper = fn() { moonvar inner = fn(x) { if (x == 0) { return 2 } else { return inner(x - 1) } } return inner(1) }
>> wrapper()
2


>> fib <- fn(n, a, b) { if (n == 0) { return a } if (n == 1) { return b } return fib(n - 1, b, a + b) }
>> fib(35, 0, 1)
9227465

Strings

>> makeGreeter <- fn(greeting) { fn(name) { greeting + " " + name + "!" } }
>> hello <- makeGreeter("Hello")
>> hello("mellum")
Hello mellum!

Arrays

>> myArray := ["Thorsten", "Ball", 28, fn(x) { x * x }]
>> myArray[0]
Thorsten
>> myArray[4 - 2]
28
>> myArray[3](2)
4

Hashes

>> myHash := {"name": "Jimmy", "age": 72, true: "yes, a boolean", 99: "correct, an integer"}
>> myHash["name"]
Jimmy
>> myHash["age"]
72
>> myHash[true]
yes, a boolean
>> myHash[99]
correct, an integer

Builtin functions

len(iterable) Returns the length of the iterable (str, array or hash).
first(iterable) Returns the first element of the array.
last(iterable) Returns the last element of the array.
push(iterable) Add an element to the array.
replace(string,element_to_replace,element_to_put) Replace something inside a string.
plsShow(element) Print something in the screen.
Strcomp(string,string) Compare the pointers of two strings.
String_Upcase(string) Upcase an entire string.
String_Split(string) Split a string into array

Development setup

After dowloading the Mellang VSCode Extension, you have to create a ".mel" file on the root of the project and specify the filename after running the "main.go".