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createAbstractFactory()

createAbstractFactory<K, Products>(families): object

Creates an abstract factory from a record of named family factories.

Each key is a family name, each value is a factory function that produces the product record for that family. All families must produce the same product shape (same keys, same signatures).

The real power is intra-family collaboration: since create returns a coherent record, products from the same family can reference each other via closure, guaranteeing compatibility without type gymnastics.

Type Parameters​

K: K extends string​

Union of family keys

Products: Products extends Record<string, (...args) => unknown>​

The record of creator functions each family produces

Parameters​

families: Record<K, Factory<Products>>​

Record mapping family keys to factory functions

Returns​

An abstract factory with create, get, and keys

create(): (key) => Products​

Create a product family by key. The factory is called each time, producing a fresh product record.

key: K
Returns: Products

get(): (key) => Option<Factory<Products>>​

Safe lookup for dynamic/runtime keys. Returns Some(factory) if the key exists, None otherwise.

key: string
Returns: Option<Factory<Products>>

keys(): () => K[]​

Returns all registered family keys.

Returns: K[]​

Since​

2.4.0

Example​

// Products that collaborate: encoder uses the separator from its family
type Codec = {
  encode: (parts: string[]) => string;
  decode: (raw: string) => string[];
};

const codecs = createAbstractFactory<"csv" | "tsv", Codec>({
  csv: () => {
    const sep = ",";
    return {
      encode: (parts) => parts.join(sep),
      decode: (raw) => raw.split(sep),
    };
  },
  tsv: () => {
    const sep = "\t";
    return {
      encode: (parts) => parts.join(sep),
      decode: (raw) => raw.split(sep),
    };
  },
});

const csv = codecs.create("csv");
csv.decode(csv.encode(["a", "b"])); // ["a", "b"] — round-trip guaranteed

Factory()<Products>​

Type

Factory<Products> = () => Products

A Factory is a zero-arg function that produces a product record. Each key in the record is a creator function for one product of the family.

Type Parameters​

Products: Products extends Record<string, (...args) => unknown>​

The record of creator functions

Returns: Products​

Since​

2.4.0