A functional, stateless philosophy treats functions as first-class values and favors functional-style techniques such as generic sequence operations. Go can support this style, but its idiomatic design emphasizes passing and retrieving state through concurrency patterns rather than pursuing functional aesthetics. section 3.2
Before Go 1.18, functions could be passed as values, but the lack of typed generic iterators limited reusable sequence operations across arbitrary types. Generics made functional-style Go more practical without making Go a functional language. section 3.2
