produceFast()

Optimized helper-based API for maximum performance (1.06-105× faster than Immer).

Signature

function produceFast<T>(base: T, recipe: (helper: FastHelper<T>) => void): T

Overview

produceFast() uses a helper-based mutation API for optimal performance:

import { produceFast } from '@sylphx/pura'

const next = produceFast(state, $ => {
  $.set(['items', 0], 999)    // Helper-based mutation
  $.push(4)                    // Array methods
  $.set(['user', 'name'], 'Jane')
})

Why use produceFast()?

• Faster: 1.06-105× faster than Immer, faster than produce()
• Explicit: Clear, intentional updates
• Optimized: Avoids proxy overhead
• Type-safe: Perfect TypeScript inference

Helper APIs

ArrayHelper

$.set(index, value)           // Update element
$.delete(index)               // Remove element
$.push(...items)              // Add to end
$.pop()                       // Remove from end
$.unshift(...items)           // Add to start
$.shift()                     // Remove from start
$.splice(start, count, ...items)
$.reverse()
$.sort(compareFn)
$.fill(value, start, end)
$.filter(fn)                  // Must return!
$.map(fn)                     // Must return!

ObjectHelper

$.set(['path', 'to', 'prop'], value)    // Deep update
$.update(['path'], updater)              // Update with function
$.delete(['path'])                       // Delete property
$.merge(['path'], partial)               // Merge object

MapHelper

$.set(key, value)
$.delete(key)
$.clear()
$.has(key)

SetHelper

$.add(value)
$.delete(value)
$.clear()
$.has(value)

Complete Documentation

See produceFast() API Guide for comprehensive documentation including:

• All helper methods
• Nested structures
• Type safety examples
• Performance tips
• Common patterns (Redux, React, Zustand)
• Comparison with produce()