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by Tade0 1878 days ago
The other day I got into a heated debate with a C# developer on the merits (or lack thereof) of adding an "I" prefix to interfaces.

Turns out in C# there's no syntactic difference between implementing an interface and inheritance, so it makes sense in C# to explicitly state that something is an interface but, arguably, only there.
1 comments
layer8 1878 days ago
The argument against “I” is that the user (client code) of an instance shouldn’t have too care whether the type of the reference is an interface or a class. Concerns of the implementor shouldn’t determine the naming visible to the client code.

Of course, it’s an established C# convention (and inspired by the naming convention for COM interfaces) so one better sticks with it, but I think the convention was a bad choice for the reason stated above.

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dragonwriter 1878 days ago
Yeah, IMV its a similar problem to the convention of prefixing DB objects with T (table) or V (view), but not as bad because refactoring between class and interface should be rare.
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Tade0 1878 days ago
100% agreed. My day job is in front-end development and we unfortunately had this convention in a few projects.

Problem is, sometimes the are changes in how types are composed and what used to be an interface can end up as a type alias and vice versa.

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