It is Really Useful in practice.
2. There is a paragraph-fill combinator, fsep, that's much like sep,
- only it keeps fitting things on one line until itc can't fit any more.
+ only it keeps fitting things on one line until it can't fit any more.
3. Some random useful extra combinators are provided.
<+> puts its arguments beside each other with a space between them,
int, integer, float, double, rational,
parens, brackets, braces, quotes, doubleQuotes,
semi, comma, colon, space, equals,
- lparen, rparen, lbrack, rbrack, lbrace, rbrace,
+ lparen, rparen, lbrack, rbrack, lbrace, rbrace, cparen,
(<>), (<+>), hcat, hsep,
($$), ($+$), vcat,
brackets p = char '[' <> p <> char ']'
braces p = char '{' <> p <> char '}'
+cparen True = parens
+cparen False = id
hcat = foldr (<>) empty
hsep = foldr (<+>) empty