Syntax Cheatsheet

RSS is RustScript's native source language. This reference follows a Rust-like path from primitive schemas through inference, ownership, control flow, generics, callable values, closures, and modules. Every syntax topic includes highlighted RSS examples.

Types and values

• Primitive Types and Literals — int, float, number, bool, string, bytes, null, and literal forms.
• Type Inference and Annotations — inferred locals, explicit schemas, numeric widening, branch merging, and contextual callable inference.
• Collections, Structs, and Optional Values — arrays, maps, tuple schemas, structs, generics, T?, optional chaining, and slices.

State and expressions

• Bindings, Mutability, and Ownership — let, let mut, assignment, moves, .copy(), borrows, fields, indexes, and captures.
• Expressions and Operators — precedence, arithmetic, comparisons, logical operators, calls, namespace calls, and access expressions.

Control and abstraction

• Control Flow and Pattern Matching — statement and expression if, match, while, ranges, range-based array traversal, borrowed map iteration, break, and continue.
• Functions, Generics, and Recursion — block and expression bodies, exports, forward calls, recursion, nested functions, generic parameters, and turbofish.
• Callables and Closures — callable schemas, function values, higher-order functions, callable collections, closures, captures, returned callables, and shared state.

Programs and tokens

• Modules, Imports, and Host Calls — source modules, aliases, relative paths, builtin and stdlib namespaces, host imports, and formatted output.
• Lexical Structure — comments, identifiers, keywords, literals, delimiters, semicolons, trailing result expressions, and .rss files.

Callable catalogs

• Builtins — generated RSS builtin namespace pages.
• Stdlibs — generated standard-library module pages.

Language boundary

The pages in this branch describe native RSS syntax. Compatibility frontends lower JavaScript-, Lua-, and Python-like source into shared compiler IR; their surface syntax belongs to the corresponding frontend, not RSS.

fn identity<T>(value: T) -> T {
    value
}
let answer: int = identity::<int>(42);
let render: fn(string) -> string = identity;
answer;
render("rss");