Is Ruby a functional language?

Question

Wikipedia says Ruby is a functional language, but I\'m not convinced. Why or why not?

Answer 1

Strictly speaking, it doesn't make sense to describe a language as "functional"; most languages are capable of functional programming. Even C++ is.

Functional style is more or less a subset of imperative language features, supported with syntactic sugar and some compiler optimizations like immutability and tail-recursion flattening,

The latter arguably is a minor implementation-specific technicality and has nothing to do with the actual language. The x64 C# 4.0 compiler does tail-recursion optimization, whereas the x86 one doesn't for whatever stupid reason.

Syntactic sugar can usually be worked around to some extent or another, especially if the language has a programmable precompiler (i.e. C's #define).

It might be slightly more meaningful to ask, "does language __ support imperative programming?", and the answer, for instance with Lisp, is "no".