extend

@rotorsoft/act-root

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@rotorsoft/act-root / act/src / extend

Function: extend()

extend<S, T>(source, schema, target?): Readonly<S & T>

Defined in: libs/act/src/utils.ts:60

Validate source against schema and return a new object that merges source over the optional target defaults. Used by config for env-var-overrides-defaults patterns; safe to call elsewhere — it never mutates target.

Type Parameters

S

S extends Record<string, unknown>

T

T extends Record<string, unknown>

Parameters

source

Readonly<S>

schema

ZodType<S>

target?

Readonly<T>

Returns

Readonly<S & T>

Example

const schema = z.object({ host: z.string(), port: z.number() });
const cfg = extend({ port: 8080 }, schema, { host: "localhost", port: 80 });
// → { host: "localhost", port: 8080 }

Throws

ValidationError if source fails the schema.