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Your search for What is a functor returned the following results:

a mapping that preservers the structure between two categories

In case you don’t know about functors; a functor is a mapping that preservers the structure between two categories.

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a function that can be manipulated as an object, or an object representing a single, generic function

A functor is a function that can be manipulated as an object, or an object representing a single, generic function.

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a class or struct object which can be 'called' like a function

A functor is a class or struct object which can be 'called' like a function.

an object that behaves like a function

A functor is an object that behaves like a function.

a morphism in the category of all categories

A functor is a morphism in the category of all categories.

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an object whose class has the operator () function

In C++, a functor is an object whose class has the operator () function.

In Functional Programming

In functional programming, a functor is essentially a construction of lifting ordinary unary functions (i.e. those with one argument) to functions between variables of new types.

just a mapping of objects and morphisms

A functor is a mapping of objects and morphisms.

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a construction of lifting ordinary unary functions () to functions between variables of new types i.e. those with one argument

In functional programming, a functor is essentially a construction of lifting ordinary unary functions (i.e. those with one argument) to functions between variables of new types.