Coming from Python

Side-by-side comparisons for Python developers.

Variables

# Python
name = "Alice"
age = 30
PI = 3.14

// Wyn
var name = "Alice"
var age = 30
const PI = 3.14

Functions

# Python
def greet(name: str) -> str:
    return f"Hello, {name}!"

// Wyn
fn greet(name: string) -> string {
    return "Hello, ${name}!"
}

Loops

# Python
for i in range(10):
    print(i)

for name in ["Alice", "Bob"]:
    print(name)

// Wyn
for i in 0..10 {
    println("${i}")
}

for name in ["Alice", "Bob"] {
    println(name)
}

Conditionals

# Python
if x > 0:
    print("positive")
elif x == 0:
    print("zero")
else:
    print("negative")

// Wyn
if x > 0 {
    println("positive")
} else if x == 0 {
    println("zero")
} else {
    println("negative")
}

Pattern Matching

# Python 3.10+
match command:
    case "quit":
        exit()
    case "hello":
        print("Hi!")
    case _:
        print("Unknown")

// Wyn
match command {
    "quit" => System.exit(0)
    "hello" => println("Hi!")
    _ => println("Unknown")
}

Structs (Classes)

# Python
class Point:
    def __init__(self, x: int, y: int):
        self.x = x
        self.y = y

    def distance(self, other: "Point") -> float:
        return ((other.x - self.x)**2 + (other.y - self.y)**2)**0.5

// Wyn
struct Point {
    x: int
    y: int

    fn distance(self, other: Point) -> float {
        var dx = (other.x - self.x) * (other.x - self.x)
        var dy = (other.y - self.y) * (other.y - self.y)
        return Math.sqrt(dx + dy)
    }
}

Concurrency

# Python (asyncio)
import asyncio

async def fetch(url):
    # ...
    return data

async def main():
    results = await asyncio.gather(
        fetch("url1"),
        fetch("url2"),
    )

// Wyn (green threads)
fn fetch(url: string) -> string {
    return Http.get(url)
}

var f1 = spawn fetch("url1")
var f2 = spawn fetch("url2")
var r1 = await f1
var r2 = await f2

Key Differences

Feature	Python	Wyn
Typing	Dynamic	Static
Compilation	Interpreted	Compiled to native
Concurrency	asyncio/GIL	Green threads (M:N)
Memory	GC	Arena allocator
Binary size	~50MB (with runtime)	~32KB
Startup	~30ms	<1ms