fn_signature(f: any) → record
Category: [reflection](builtinsreflection)_
Describe a function's parameters and return type. Pass a function value, or a built-in's name as a string.
| Parameter | Type | Description | Remarks |
|---|---|---|---|
| f | any | A function value, or the name of a built-in as a utf8 string. | — |
| returns | record | A record { doc, params: [{name, type, doc}], return_type, return_doc, signature, is_builtin }. | — |
wcl
fn_signature("map") // describe the map builtin → { signature: "fn(xs: [T], ...) -> [U]", ... }