How to distinguish between a macro and an imported function?

Is there any easy way to tell whether a given bit of code is a function or a macro? I’m thinking of stuff like plug in Phoenix… if you use some other module, it’s not clear what might be happening under the hood. Does anyone have any tips for this? Thanks!

Should be marked as either function or macro in the documentation.

In iex you can use h/1 to check. The headline will either say def or defmacro.