@effect-ts/system/_src/Managed/methods/allocate.ts

Effect-TS is a zero dependency set of libraries to write highly productive, purely functional TypeScript at scale.

// ets_tracing: off

import * as Tp from "../../Collections/Immutable/Tuple/index.js"
import * as T from "../deps.js"
import type { Managed } from "../managed.js"
import { makeReleaseMap, releaseAll } from "../ReleaseMap/index.js"

export class Allocation<A> {
  constructor(readonly value: A, readonly release: T.UIO<void>) {}
}

/**
 * Allocates the managed for future usage & release.
 *
 * Note: in case of failures during acquisition resources that
 * have been acquired will be immediately released. In case the
 * managed succeeds in acquiring all the resources an Allocation
 * will be returned and it is up to the caller to ensure invokation
 * of `release`, if that is not done resources will not be released.
 */
export function allocate<R, E, A>(self: Managed<R, E, A>) {
  return T.chain_(makeReleaseMap, (rm) =>
    T.foldCauseM_(
      T.provideSome_(self.effect, (r: R) => Tp.tuple(r, rm)),
      (cause) =>
        T.chain_(releaseAll(T.exitHalt(cause), T.sequential)(rm), () => T.halt(cause)),
      ({ tuple: [_, a] }) =>
        T.succeed(
          new Allocation(
            a,
            T.descriptorWith((d) => releaseAll(T.exitInterrupt(d.id), T.sequential)(rm))
          )
        )
    )
  )
}