Oyinkansola Awosan
Mar 29, 2022 ⋅ 4 min read

How to use type guards in TypeScript

Oyinkansola Awosan I'm a fun techie and passionate technical writer interested in data science, machine learning, cloud engineering, and blockchain technologies.

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6 Replies to "How to use type guards in TypeScript"

  1. The section on the typeof operator is somewhat incorrect. I can be string, number, boolean, or symbol ALONG WITH function, object, and bigint.

  2. The section “The typeof type guard” may mislead the readers unless the author corrects those type with the lowercased types.

  3. Crazy language… The only way to really check for union typed classInstance is to have some unique filed name in it and do “if (uniqueFieldName in classInstance)”… *blarghhhhh

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