Function (helping-js/core/function)

Higher-order helpers: resolve getters, limit call count, poll for changes, bind this, async finally, compose pipelines, and map a tree of plain objects/arrays.

Imports

import {
  resolveValueOrGetter,
  executeWithCount,
  watchChange,
  bindContext,
  applyFinally,
  joinFunctionsByResult,
  joinFunctionsByNext,
  mapObjectTree,
} from 'helping-js/core/function'

API

Function	Role
resolveValueOrGetter(x, ...args)	Call if function, else return value
executeWithCount(fn, count)	Stops returning results after count calls
watchChange(getValue, fn, intervalMs?)	setInterval poll; calls fn when reference changes
bindContext(fn, ctx)	fn.bind(ctx)
applyFinally(asyncFn, onFinally)	Async wrapper; runs onFinally after completion
joinFunctionsByResult(...fns)	Last result wins (sequential void-ish)
joinFunctionsByNext(...fns)	Left-to-right r = fn(r) reducer
mapObjectTree(obj, mapper)	Immutable map over nested plain data

Samples

Config or thunk

const port = resolveValueOrGetter(cfg.port, cfg)

Map API payload

const next = mapObjectTree(payload, (value, key) =>
  key === 'email' ? String(value).trim() : value
)

Express middleware with cleanup

import { applyFinally } from 'helping-js/core/function'

const handler = applyFinally(async (req, res) => {
  await work()
}, () => release(req.id))

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