Syntax

Blocks

A block is a sequence of statements following a :. Indentation is conventional but not enforced.

def greet(String name):
    print("hello", name)
    print("goodbye", name)

end is not required when the block occupies its own lines. It is only used to close a block that is written inline on the same line as its header:

if(x > 0): print("positive") end

while(running): tick() end

def noop: end

Without end, the block runs until the next statement at the same syntactic level.

Lambdas never use end - their body is always a single expression:

let double = lambda(Int x) -> Int: x * 2

Line comments start with //.

// this is a comment
let x = 1  // inline comment

Block comments use /* */ and may span multiple lines.

/* this is a
block comment */

let x = /* inline block */ 1

Embed expressions directly in strings using ${...}:

let name = "Alice"
let age = 30
print("Hello ${name}, you are ${age} years old!")

Any expression works inside ${}:

let x = 10
print("double is ${x * 2}")
print("type: ${x.toString()}")

Semicolons are optional and ignored. They may be used for style or to separate statements on one line.

let x = 1; let y = 2

Identifiers start with a letter or underscore and contain letters, digits, and underscores. Type names conventionally start with an uppercase letter.