head package:text

O(1) Returns the first character of a Text, which must be non-empty. This is a partial function, consider using uncons instead.

O(1) Returns the first character of a Stream Char, which must be non-empty. This is a partial function, consider using uncons. Properties

head . stream = head

The memory management overhead. Currently this is tuned for GHC only.

O(1) A variant of head for non-empty Text. unsafeHead omits the check for the empty case, so there is an obligation on the programmer to provide a proof that the Text is non-empty.