+ getHeaders ∷ a → Headers
+ setHeaders ∷ a → Headers → a
+
+ modifyHeaders ∷ (Headers → Headers) → a → a
+ {-# INLINE modifyHeaders #-}
+ modifyHeaders = (setHeaders ⊛) ∘ (∘ getHeaders)
+
+ getHeader ∷ CIAscii → a → Maybe Ascii
+ {-# INLINE getHeader #-}
+ getHeader = (∘ getHeaders) ∘ lookup
+
+ hasHeader ∷ CIAscii → a → Bool
+ {-# INLINE hasHeader #-}
+ hasHeader = (∘ getHeaders) ∘ member
+
+ getCIHeader ∷ CIAscii → a → Maybe CIAscii
+ {-# INLINE getCIHeader #-}
+ getCIHeader = ((cs <$>) ∘) ∘ getHeader
+
+ deleteHeader ∷ CIAscii → a → a
+ {-# INLINE deleteHeader #-}
+ deleteHeader = modifyHeaders ∘ delete
+
+ setHeader ∷ CIAscii → Ascii → a → a
+ {-# INLINE setHeader #-}
+ setHeader = (modifyHeaders ∘) ∘ insertWith const