|Portability||non-portable (GHC Extensions)|
GHC type definitions. Use GHC.Exts from the base package instead of importing this module directly.
The character type
Char is an enumeration whose values represent
Unicode (or equivalently ISO/IEC 10646) characters
(see http://www.unicode.org/ for details).
This set extends the ISO 8859-1 (Latin-1) character set
(the first 256 charachers), which is itself an extension of the ASCII
character set (the first 128 characters).
A character literal in Haskell has type
A fixed-precision integer type with at least the range
[-2^29 .. 2^29-1].
The exact range for a given implementation can be determined by using
Prelude.maxBound from the
Single-precision floating point numbers. It is desirable that this type be at least equal in range and precision to the IEEE single-precision type.
Double-precision floating point numbers. It is desirable that this type be at least equal in range and precision to the IEEE double-precision type.
A value of type
is a computation which, when performed,
does some I/O before returning a value of type
There is really only one way to "perform" an I/O action: bind it to
Main.main in your program. When your program is run, the I/O will
be performed. It isn't possible to perform I/O from an arbitrary
function, unless that function is itself in the
IO monad and called
at some point, directly or indirectly, from