Note: The interesting part begins at post #9 . Solution in post #23 . . . . [image] Meaning of {T} [image] Meaning of {T} function zca{Int32}(o::Whiten{Int32}) function zca{Float64}(o::Whiten{Float64}) That is very ill-advised. That is not an advice to the user (it would defeat the us…

Could you use generated functions? Not sure if this is recommended, or indeed if it will work. @generated function myfunc{T}(a::T) if method_exists(feature, (T,)) :(_myfunc(a)) else :(error("$T does not have feature")) end end function _myfunc(a) println("_myfunc c…

[image] Meaning of {T} As a moderator, you can always move the resulting mess into a separate thread or even in the trash. The ideal would be for someone to isolate the correct information in this thread and combine it into a single post or even create a relevant FAQ entry and link there. Idea…

[image] Meaning of {T} nor assert that you speak on behalf of the average reader That’s the opposite of what I said: [image] Meaning of {T} I’m not talking on behalf of anyone but myself And that should be self-evident, but I have to clarify even that. I’m not the average user and nobod…

[image] Meaning of {T} Strict typing of functions is kind of a new user trap for this reason: it’s just for throwing errors, but has a feel that it might improve performance. I disagree. It’s not just for throwing errors, but like types in general it serve as useful, compiler checked documenta…

[image] Meaning of {T} but I’d put types in many places even if it made the code a bit slower. IME your unintended uses for loose typing end up being unintended consequences. Can you give an example of ‘unintended consequences’? For me such type annotations only distract from the code. I wo…

[image] Meaning of {T} Can you give an example of ‘unintended consequences’? Consider this, from Base. Let’s say using the function in you can’t remember if the collection or the item goes first: a = ["a", "b", "c"] b = "b" in(a,b) # false in(b,a) # true No errors, just an unintended result. …

[image] Meaning of {T} I disagree. It’s not just for throwing errors, but like types in general it serve as useful, compiler checked documentation. True, documentation is a case that I overlooked. (In fact, it’s probably the only use for putting a return type on a type-stable function since if…

I have to disagree that this is an unintended result. It is indeed the case that ["a", "b", "c"] does not occur in "b". My opposition to overtyping of functions is not out of disdain for compiler-checked documentation, but out of disdain for needless loss of generality. Further, I disagree that typ…

[image] Meaning of {T} Can you give an example of ‘unintended consequences’? Every type error that is not caught at compile time is an unintended consequence. I could make up trivial examples, like stuffing a string into a floating point array if some flag is true, or calling a function with d…

These are good examples of why restricting types in a method signature is useful and I don’t think anyone disagree with that. However, it is still true that overly constraint the type is a known beginners trap. Take your floating point array example. You should not allow such insertion to be called…

[image] Meaning of {T} But restricting types on functions can have some downsides that duck-typing fixes. Here’s a few examples: Excellent examples! But let me ask a question here. Say you’d written your iterative solver over matrices with over-specific types. Do you really think it’s unlikely…

Strict typing and restricting types in a method's signature

General Usage

mauro3 November 30, 2016, 10:12pm 22

Maybe check this again.

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Strict typing and restricting types in a method's signature

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