you cant reuse names with top line functions:

    package hello
    
    type cat int
    
    func greet(c cat) cat {
       return c + 1
    }
    
    type dog string
    
    func greet(d dog) dog { // greet redeclared in this block
       return d + "one"
    }

but you can with methods:

    package hello
    
    type cat int
    
    func (c cat) greet() cat {
       return c + 1
    }
    
    type dog string
    
    func (d dog) greet() dog {
       return d + "one"
    }