svelte-previous

• Purpose: Svelte stores that remember previous values, enabling actions dependent on previous states (e.g., transitions between old and new values).
• Target Audience: Svelte developers needing state management with history tracking.
• Key Features:
  • Tracks one or more previous values via withPrevious.
  • Returns a tuple of writable (current) and readable (previous) stores.
  • Supports customization through options like numToTrack, initPrevious, requireChange, and custom equality checks (isEqual).
• Svelte Support: Primarily designed for Svelte, leveraging its reactivity system.
• Demo: REPL demo .
• Options:
  • numToTrack: Number of previous values to store (default: 1).
  • initPrevious: Initialize previous values (newest to oldest).
  • requireChange: Only update on value changes (default: true).
  • isEqual: Custom equality function (default: ===).