Currying

Mon, 01 Jan 0001 00:00:00 +0000

@statili/fp ·v0.0.2-beta.0 ·1 export

# curry function

signature

curry<T extends (...args: any[]) => any>(fn: T): Curried<Args<T>, Return<T>>

Creates a curried version of a function. A curried function can be called with all arguments at once for immediate execution, or with arguments one at a time (or in chunks) for partial application, returning new functions until all arguments are received.

This utility favors “data-last” arguments for better composability, meaning the data array should typically be the last parameter of the function being curried.

Type parameters

T: The type of the function to curry.

Parameters

Name	Type	Description
fn	T	The function to curry.

Returns

Curried<Args<T>, Return<T>>

A new function that is a curried version of fn.

Example

import { curry } from './curry';

// Example: A simple sum function with data-last
function sum(offset: number, numbers: number[]): number {
return numbers.reduce((acc, val) => acc + val + offset, 0);
}

const curriedSum = curry(sum);

// Partial application (curried form)
const sumWithOffsetOfTen = curriedSum(10);
console.log(sumWithOffsetOfTen([1, 2, 3])); // Output: 16

// Immediate execution (all arguments at once)
console.log(curriedSum(5, [1, 2, 3])); // Output: 11

// Example with a function returning a complex type (like LinearRegressionResult)
type Point = { x: number; y: number };
type RegressionResult = { ok: boolean, m?: number, b?: number, error?: string };

function _calculateRegression(options: { includeRSquared: boolean }, data: Point[]): RegressionResult {
// ... actual calculation logic ...
return { ok: true, m: 1, b: 0 };
}

const calculateRegression = curry(_calculateRegression);

// Partial application
const regressionWithRSquared = calculateRegression({ includeRSquared: true });
const resultPartial = regressionWithRSquared([{ x: 1, y: 1 }]);
console.log(resultPartial);

// Immediate execution
const resultImmediate = calculateRegression({ includeRSquared: false }, [{ x: 1, y: 1 }]);
console.log(resultImmediate);

Pipe & Compose

Mon, 01 Jan 0001 00:00:00 +0000

@statili/fp ·v0.0.2-beta.0 ·1 export

# pipe function

packages/fp/src/pipe.ts:19

signatures

pipe<A, B>(f1: (input: A) => B): (input: A) => B
pipe<A, B, C>(f1: (input: A) => B, f2: (input: B) => C): (input: A) => C
pipe<A, B, C, D>(f1: (input: A) => B, f2: (input: B) => C, f3: (input: C) => D): (input: A) => D
pipe<A, B, C, D, E>(f1: (input: A) => B, f2: (input: B) => C, f3: (input: C) => D, f4: (input: D) => E): (input: A) => E
pipe<A, B, C, D, E, F>(f1: (input: A) => B, f2: (input: B) => C, f3: (input: C) => D, f4: (input: D) => E, f5: (input: E) => F): (input: A) => F
pipe<A, B, C, D, E, F, G>(f1: (input: A) => B, f2: (input: B) => C, f3: (input: C) => D, f4: (input: D) => E, f5: (input: E) => F, f6: (input: F) => G): (input: A) => G
pipe<A, B, C, D, E, F, G, H>(f1: (input: A) => B, f2: (input: B) => C, f3: (input: C) => D, f4: (input: D) => E, f5: (input: E) => F, f6: (input: F) => G, f7: (input: G) => H): (input: A) => H
pipe<F extends readonly [(...args: any[]) => any, ...Array<(arg: any) => any>]>(...fns: F): (input: PipeInput<F>) => PipeReturn<F>

Parameters

Name	Type	Description
f1	(input: A) => B	—
f2	(input: B) => C	—
f3	(input: C) => D	—
f4	(input: D) => E	—
f5	(input: E) => F	—
f6	(input: F) => G	—
f7	(input: G) => H	—

Returns

(input: A) => H

Functional Primitives on statili

Currying

# curry function

Type parameters

Parameters

Returns

Example

Pipe & Compose

# pipe function

Parameters

Returns