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Lesson 31 of 48
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JAVASCRIPT CLIMBSChapter 6 · JS Async and Errors

Catching errors with try-catch

Use try...catch to intercept errors. You can throw custom errors using the throw statement.

Worked example

How it reads

  • throw new Error(...) creates and fires an error object
  • catch (error) receives the thrown error
Cloud tip: You can also use a finally block to execute code regardless of whether an error was thrown.
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JAVASCRIPT
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YOUR TURN

Write checkAltitude(n) that throws new Error("too low") when n is below 100. Call it with 40 inside try...catch and log error: too low.

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