pipe

Passes a value through unary functions from left to right.

Code

pipe.ts

export type UnaryFunction<in Input, out Output> = (
  this: void,
  value: Input
) => Output;

export type Pipe = {
  <A>(value: A): A;
  <A, B>(value: A, ab: UnaryFunction<A, B>): B;
  <A, B, C>(
    value: A,
    ab: UnaryFunction<A, B>,
    bc: UnaryFunction<B, C>
  ): C;
  <A, B, C, D>(
    value: A,
    ab: UnaryFunction<A, B>,
    bc: UnaryFunction<B, C>,
    cd: UnaryFunction<C, D>
  ): D;
  <A, B, C, D, E>(
    value: A,
    ab: UnaryFunction<A, B>,
    bc: UnaryFunction<B, C>,
    cd: UnaryFunction<C, D>,
    de: UnaryFunction<D, E>
  ): E;
  <A, B, C, D, E, F>(
    value: A,
    ab: UnaryFunction<A, B>,
    bc: UnaryFunction<B, C>,
    cd: UnaryFunction<C, D>,
    de: UnaryFunction<D, E>,
    ef: UnaryFunction<E, F>
  ): F;
  <A, B, C, D, E, F, G>(
    value: A,
    ab: UnaryFunction<A, B>,
    bc: UnaryFunction<B, C>,
    cd: UnaryFunction<C, D>,
    de: UnaryFunction<D, E>,
    ef: UnaryFunction<E, F>,
    fg: UnaryFunction<F, G>
  ): G;
  <A, B, C, D, E, F, G, H>(
    value: A,
    ab: UnaryFunction<A, B>,
    bc: UnaryFunction<B, C>,
    cd: UnaryFunction<C, D>,
    de: UnaryFunction<D, E>,
    ef: UnaryFunction<E, F>,
    fg: UnaryFunction<F, G>,
    gh: UnaryFunction<G, H>
  ): H;
  <A, B, C, D, E, F, G, H, I>(
    value: A,
    ab: UnaryFunction<A, B>,
    bc: UnaryFunction<B, C>,
    cd: UnaryFunction<C, D>,
    de: UnaryFunction<D, E>,
    ef: UnaryFunction<E, F>,
    fg: UnaryFunction<F, G>,
    gh: UnaryFunction<G, H>,
    hi: UnaryFunction<H, I>
  ): I;
  <A, B, C, D, E, F, G, H, I, J>(
    value: A,
    ab: UnaryFunction<A, B>,
    bc: UnaryFunction<B, C>,
    cd: UnaryFunction<C, D>,
    de: UnaryFunction<D, E>,
    ef: UnaryFunction<E, F>,
    fg: UnaryFunction<F, G>,
    gh: UnaryFunction<G, H>,
    hi: UnaryFunction<H, I>,
    ij: UnaryFunction<I, J>
  ): J;
  <A, B, C, D, E, F, G, H, I, J, K>(
    value: A,
    ab: UnaryFunction<A, B>,
    bc: UnaryFunction<B, C>,
    cd: UnaryFunction<C, D>,
    de: UnaryFunction<D, E>,
    ef: UnaryFunction<E, F>,
    fg: UnaryFunction<F, G>,
    gh: UnaryFunction<G, H>,
    hi: UnaryFunction<H, I>,
    ij: UnaryFunction<I, J>,
    jk: UnaryFunction<J, K>
  ): K;
};

/** Passes a value through up to ten type-compatible unary functions. */
export const pipe: Pipe = (
  value: unknown,
  ...functions: Array<UnaryFunction<unknown, unknown>>
): unknown => {
  return functions.reduce(
    (current, transform) => transform(current),
    value
  );
};

Download

wget

Terminal

wget -O src/lib/pipe.ts https://raw.githubusercontent.com/jrTilak/lazykit/HEAD/registry/functions/pipe.ts

degit

Terminal

temp_dir="$(mktemp -d)" && bunx degit jrTilak/lazykit/registry/functions "$temp_dir" && mv "$temp_dir/pipe.ts" src/lib/pipe.ts && rm -r "$temp_dir"

Examples

pipe.example.ts

import { pipe } from "./pipe";

const label = pipe(
  21,
  (value) => value * 2,
  String,
  (value) => `Result: ${value}`
);

const summaryLength = pipe(
  ["Ada", "Grace", "Linus"],
  (names) => names.join(", "),
  (names) => `Contributors: ${names}`,
  (summary) => summary.length
);

Props

• value — Initial value.
• Up to ten unary transformation functions can be chained; each input is inferred from the previous return value.
• Returns the final transformed value.