@effect-ts/system/_src/Collections/Immutable/Chunk/api/takeWhileEffect.ts

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

// ets_tracing: off

import * as core from "../../../../Effect/core.js"
import type { Effect } from "../../../../Effect/effect.js"
import * as coreMap from "../../../../Effect/map.js"
import * as Chunk from "../core.js"
import { concreteId } from "../definition.js"

/**
 * Takes all elements so long as the effectual predicate returns true.
 */
export function takeWhileEffect_<R, E, A>(
  self: Chunk.Chunk<A>,
  f: (a: A) => Effect<R, E, boolean>
): Effect<R, E, Chunk.Chunk<A>> {
  return core.suspend(() => {
    const iterator = concreteId(self).arrayLikeIterator()
    let next
    let taking: Effect<R, E, boolean> = core.succeed(true)
    let builder = Chunk.empty<A>()

    while ((next = iterator.next()) && !next.done) {
      const array = next.value
      const len = array.length
      let i = 0
      while (i < len) {
        const a = array[i]!
        taking = core.chain_(taking, (d) =>
          coreMap.map_(d ? f(a) : core.succeed(false), (b) => {
            if (b) {
              builder = Chunk.append_(builder, a)
            }
            return b
          })
        )
        i++
      }
    }
    return coreMap.map_(taking, () => builder)
  })
}

/**
 * Takes all elements so long as the effectual predicate returns true.
 *
 * @ets_data_first takeWhileEffect_
 */
export function takeWhileEffect<R, E, A>(
  f: (a: A) => Effect<R, E, boolean>
): (self: Chunk.Chunk<A>) => Effect<R, E, Chunk.Chunk<A>> {
  return (self) => takeWhileEffect_(self, f)
}