A first-class function is not a particular kind of function. All functions in Python are first-class functions. To say that functions are first-class in a certain programming language means that they can be passed around and manipulated similarly to how you would pass around and manipulate other kinds of objects (like integers or strings). You … Read more
Ruby doesn’t have functions. It only has methods (which aren’t first-class) and Procs which are first-class, but are not associated with any object. So, this is a method: def foo(bar) puts bar end foo(‘Hello’) # Hello Oh, and, yes, this is a real method, not a top-level function or procedure or something. Methods defined at … Read more
A language that considers procedures to be “first-class” allows functions to be passed around just like any other value. Languages like Java 7 (and earlier) and C “kind of” have this capability: C allows function pointers to be passed around, but you can’t dynamically define a function in those languages and suddenly pass that somewhere … Read more
You simply don’t call the function. >>> def x(): >>> print(20) >>> y = x >>> y() 20 The brackets tell Python that you are calling the function, so when you put them there, it calls the function and assigns y the value returned by x (which in this case is None).
Just pass it in like any other parameter: def a(x): return “a(%s)” % (x,) def b(f,x): return f(x) print b(a,10)