Why do people prefer list comprehensions like
(for [x '(1 2 3)] (* 2 x)) instead of (map #(* %1 2) '(1 2 3))?
Are there benefits to this kind of programming?
1. Is it more readable?
2. Is it faster in some cases?
3. Is it better for certain kinds of operations and data structures?
For your given example, there are no benefits; but in general, for is useful when you're joining two (or more) sequences, or when you need to do some filtering - a for with :let and :when is usually more readable than a chain of nested map and filter.
list comprehensions are used for cases where you need to iterate through sequences in more complex ways. in your example they are the same so I would recoment map because its easier to read.
map cant gets ugly for do this for example:
(for [x '(1 2 3) y '(3 2 1)] (* 2 x y))
List comprehensions are merely "syntactic sugar" over standard functional programs but they give an intuitive reading of common operations over lists. -- Guy Lapalme
Their only intent is better readability. Don't expect any significant performance improvement by using them.
This paper give some insights into implementing List comprehensions in Lisp like languages.