# Helper Libraries

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General purpose utilities and behaviors — routing, theming, localization, sorting, drag-and-drop, and other building blocks.

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- [ab-test](/ab-test/)
- [drag & drop](/drag-and-drop/)
- [hash-state](/hash-state/)
- [live-theme](/live-theme/)
- [localize](/localize/)
- [makeSorter](/make-sorter/)
- [naturalCompare](/natural-compare/)
- [router](/router/)
- [scriptTag & styleSheet](/via-tag/)
- [theme](/theme/)
- [trackDrag](/track-drag/)
- [valueRenderer](/value-renderer/)
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