React type.toUpperCase is not a function

Kevin Simper
Jun 30, 2015 · 1 min read

If you get this error

type.toUpperCase is not a function

then you probrably forgot to use

module.exports = MyNewComponent

It can not be easy to spot, because the error does not show where it actually is, you see something like this

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So before you pull your hair out (as I have done), go back and look at the latest component you made, and check if you export the module correct.

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