Teeny Language Reference

Literals: numbers, strings, arrays

Teeny supports numeric literals, string literals and array literals.

let n = 3.14
let msg = "hello"
let xs = [1, 2, 3]
print msg

• Numbers

  Integers and decimals

  • 10
  • 42
  • 3.14

• Strings

  Double or single quoted strings

  • "hello"
  • 'world'

• Arrays

  Array literals using [ ... ]

  • [1, 2, 3]
  • ["hello", "world"]

Variables and assignment

Use `let` to declare variables. You can also reassign existing variables and array elements.

let x = 10
let y = 20
x = x + 1
let sum = x + y
print sum

Expressions

Expressions can include arithmetic operators (+, -, *, /) and comparisons (<, >).

let a = 1 + 2
let b = 3 * 4
let bigger = b > 10
print bigger

Indexing and member access

Index into arrays using `arr[0]` syntax.

let xs = [1, 2, 3]
xs[0] = 10
print xs[0]

Control flow: if, while, for

Control flow uses parentheses after the keyword and a single statement as the body.

• if (condition) statement [else statement]

  Single-statement form (no block parsing yet)

  • if(x > 5) return 5;
  • if(x = 5) return 5;

• while (condition) statement

  Single-statement form

  • while (true) return 5;
  • while (x > 5) return 5;

• for (init; test; update) statement

  Block parsing with { ... } is not supported yet

  • for(let i = 0; i < 10; i++) return 5
  • for(; i < 10; i++) return 5

• Try switching x around in the conditions and watch how the AST changes.
• For loops: keep the body as a single statement (e.g. `return ...`).