Logo Questions Linux Laravel Mysql Ubuntu Git Menu
 

see why "type does not conform to protocol" in Xcode (swift)

I frequently have relatively complicated protocols with associatedType constraints, are used in generics, are used by CoreData type extensions, etc. I therefore relatively frequently get the error: Type .. does not conform to protocol .... I usually can figure this out after a while, but the error message is really unhelpful -- and usually, if the problem is a minor typo in the signature of a method or something, the bug takes a little while to find. With Java interfaces, IDEs will often report something like method ... not implemented or something, so I know which method to look at in closer detail.

is there a way to make Xcode report details about the members of the protocol which are missing from the conforming type?

like image 419
qqq Avatar asked Apr 26 '16 18:04

qqq


1 Answers

When you get that error, click on the arrow to expand it. It will show the required function(s) that are missing.

Here is an example where I implement UITableViewDataSource but I have forgot to provide the "cellForRowAtIndexPath" function.

enter image description here

like image 145
Michael Peterson Avatar answered Nov 01 '22 17:11

Michael Peterson