2018年6月29日 · I keep hearing a lot about functors in C++. Can someone give me an overview as to what they are and in what cases they would be useful?

2010年1月9日 · A functor is a function which maps objects and morphisms from one category to objects and morphisms in another. Least that's how I understand it. What that means exactly …

2012年5月7日 · As it is, what is the difference between functor and function? As far as I know, they look really similar. And is functor used in set theory? I know that function is used in set …

2011年8月28日 · A functor that is Applicative but not a Monad because laws cannot be satisfied even though the type signature of bind can be implemented. This example has generated …

2016年6月4日 · For one, the functor can contain internal state; a state that is valid for this invocation of the function object only. You could add static variables to your function, but those …

The Tor functors are the derived functors of the tensor product. The starting observation is that if 0 → M′ → M → M′′ → 0 is a ses of modules and N is any module (let's work over a fixed …

2022年6月20日 · The takeaway is as follows: It’s safe to think of a representable functor as being a hom functor for the purpose of almost any proof or construction. The interesting thing about …

2023年9月24日 · In sum, the question is whether or not to mean functor as a property of couples of functions or as to couple of functions with built-in domain and codomain (which are …

2017年7月22日 · A functor takes a pure function (and a functorial value) whereas a monad takes a Kleisli arrow, i.e. a function that returns a monad (and a monadic value). Hence you can …

2009年6月2日 · But I just can't figure out the proper syntax to specify template parameters with a parameterless functor. Is there a proper way to do this? Obviously, this code would work since …