+-- |Convert an 'HttpVersion' to 'AsciiBuilder'.
+printHttpVersion ∷ HttpVersion → AsciiBuilder
+printHttpVersion v
+ = case v of
+ -- Optimisation for special cases.
+ HttpVersion 1 0 → A.toAsciiBuilder "HTTP/1.0"
+ HttpVersion 1 1 → A.toAsciiBuilder "HTTP/1.1"
+ -- General cases.
+ HttpVersion maj min
+ → A.toAsciiBuilder "HTTP/" ⊕
+ A.unsafeFromBuilder (BT.integral maj) ⊕
+ A.toAsciiBuilder "." ⊕
+ A.unsafeFromBuilder (BT.integral min)
+
+-- |'Parser' for an 'HttpVersion'.