Generic Method with # Methods

General Usage
1

What exactly does “with # methods” mean? Here are some results that really confuse me.

function sayhi(x,y)
    x+y
end

Result: sayhi (generic function with 3 methods)

function f(x,y)
    x+y
end

Result: f (generic function with 1 method)

2

The number of methods is the number different possible places you end up when calling a function. This is because with multiple dispatch some functions (like +) are defined in many different ways for different type combinations.

3

Try to restart Julia. You may have some old definitions lying around.

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4

You can use methods() to see a list of the methods for a given function:

julia> function f(x, y)
         x + y
       end
f (generic function with 1 method)

julia> methods(f)
# 1 method for generic function "f":
[1] f(x, y) in Main at REPL[1]:2

julia> function f(x)
         x + 2
       end
f (generic function with 2 methods)

julia> methods(f)
# 2 methods for generic function "f":
[1] f(x) in Main at REPL[3]:2
[2] f(x, y) in Main at REPL[1]:2
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