Type Mappings

Every Rust type is automatically mapped to its TypeScript equivalent during code generation. Here's the complete reference.

Rust	TypeScript	Notes
`String`, `&str`, `char`	`string`
`i8`–`i128`, `u8`–`u128`, `f32`, `f64`	`number`	or `bigint` via `bigint_types`
`bool`	`boolean`
`()`	`void`	no-input procedures
`Vec<T>`, `HashSet<T>`, `BTreeSet<T>`	`T[]`	also `Array<T>` in generic positions
`Option<T>`	`T \| null`	with `serde(default)`: `field?: T \| null`
`HashMap<K, V>`, `BTreeMap<K, V>`	`Record<K, V>`
`Box<T>`, `Arc<T>`, `Rc<T>`, `Cow<T>`	`T`	transparent unwrap
`(A, B, C)`	`[A, B, C]`	tuples
`[T; N]`	`T[]`	fixed-size arrays
`Result<T, E>`	`T`	`Ok(T)` unwrapped; `Err(E)` serialized as JSON and thrown as `RpcError` (status 500)
`struct`	`interface`
`enum` (unit variants)	`"A" \| "B"`	string union
`enum` (data variants)	`{ A: T } \| ...`	see Serde Support for tagging
Newtype `struct Id(String)`	`type Id = string`	or branded with `branded_newtypes`

Try it

A single struct with every mapping from the table above. Click Fetch to see live values.