ord -package:sbv -package:leancheck -package:cabal-install-solver -package:base-prelude package:base-compat

The Ord class is used for totally ordered datatypes. Instances of Ord can be derived for any user-defined datatype whose constituent types are in Ord. The declared order of the constructors in the data declaration determines the ordering in derived Ord instances. The Ordering datatype allows a single comparison to determine the precise ordering of two objects. Ord, as defined by the Haskell report, implements a total order and has the following properties:

• Comparability x <= y || y <= x = True
• Transitivity if x <= y && y <= z = True, then x <= z = True
• Reflexivity x <= x = True
• Antisymmetry if x <= y && y <= x = True, then x == y = True

The following operator interactions are expected to hold:

1. x >= y = y <= x
2. x < y = x <= y && x /= y
3. x > y = y < x
4. x < y = compare x y == LT
5. x > y = compare x y == GT
6. x == y = compare x y == EQ
7. min x y == if x <= y then x else y = True
8. max x y == if x >= y then x else y = True

Note that (7.) and (8.) do not require min and max to return either of their arguments. The result is merely required to equal one of the arguments in terms of (==). Minimal complete definition: either compare or <=. Using compare can be more efficient for complex types.

unwords joins words with separating spaces (U+0020 SPACE).

>>> unwords ["Lorem", "ipsum", "dolor"]
"Lorem ipsum dolor"

unwords is neither left nor right inverse of words:

>>> words (unwords [" "])
[]

>>> unwords (words "foo\nbar")
"foo bar"

words breaks a string up into a list of words, which were delimited by white space (as defined by isSpace). This function trims any white spaces at the beginning and at the end.

>>> words "Lorem ipsum\ndolor"
["Lorem","ipsum","dolor"]

>>> words " foo bar "
["foo","bar"]

A Word is an unsigned integral type, with the same size as Int.