Loop all pairs

Let's say I have this array:

{a, b, c, d, e}

How can I look through all the possible pairs?

a, b
a, c
a, d
a, e
b, c
b, d
b, e
c, d
c, e
d, e

Fictional language syntax please.

Prelude> let a = "ABCDE" in [ (x,y) | x <- a, y <- a, x < y ]
[('A','B'),('A','C'),('A','D'),('A','E'),('B','C'),('B','D'),('B','E'),('C','D'),('C','E'),('D','E')]