Language Overview

Syntax Summary

Keywords

• fn — function declaration (replaces function; function also supported)
• let — mutable variable declaration (block-scoped)
• const — immutable variable declaration (block-scoped, error on reassignment)
• if, else, while, for, return, break, continue, switch, case, default, do, throw, try, catch, typeof
• true, false, null

Literals

• Numbers: 1, 1.5, 0.5
• Strings: "hello", 'world' (escapes: \n, \r, \t, \\, \", \') — .length returns character count
• Booleans: true, false
• Null: null
• Arrays: [1, 2, 3] — .length returns element count
• Objects: { x: 1, y: 2 } (plain objects, fixed keys at parse time)

Operators

Control Flow

• if (cond) stmt / if (cond) stmt else stmt
• while (cond) stmt / do stmt while (cond)
• for (init; cond; update) stmt — C-style
• for (let x of arr) — iterate arrays and strings
• for (const x of arr) — iterate with immutable binding
• switch (expr) { case val: stmt... default: stmt }
• break, continue, return expr
• throw expr / try stmt catch (e) stmt
• typeof expr — returns "number", "string", "boolean", "null", "object", "function" (Tish uses "null" for null; JS uses "object")
• void expr — evaluates expr, returns null (Tish uses null instead of JS undefined)
• Postfix ++ / -- on identifiers

Blocks: { stmt; stmt } or indentation (tab/space).

Semantics

• Block scope: Variables declared with let/const are block-scoped. No hoisting.
• Immutability: const bindings cannot be reassigned (like JavaScript).
• Strict equality only: === / !==; no loose coercion.
• No this: Use explicit parameters.
• No prototypes: Plain objects and arrays; fixed shapes.
• Closures: Functions capture by name; lexical scope.

Next

• Tish vs JavaScript — Differences and additions from JavaScript
• Syntax — Full syntax reference
• Type Annotations — Optional TypeScript-style types