Glossary coding Term Page
Navigation Guard
Pre-route check that enforces auth, unsaved warnings, or other policies.
Core Idea
A navigation guard hooks into the routing cycle before rendering the next view. It can confirm unsaved data, verify authentication, or prompt the user, and only proceed when the condition passes.
Why It Matters Here
Mathbong’s routing lessons treat guards as the final layer once hash routers and the History API are familiar. Guards make the DIY router feel closer to framework routers while keeping the code readable.