Thu Feb 24 17:58:36 CET 2011
:info [<name> ...] display information about the given names
By "names", it's referring to existing definitions, either in imported
modules or defined within ghci using let, e.g.:
Prelude> let foo =3D "foo"
Prelude> :i foo
foo :: [Char] -- Defined at <interactive>:1:5-7
So, ":info g" would work; as would ":info g T" (by getting the info of
both g and T _separately_).. But ":info g 4" doesn't because of the
_4_, as it is a literal value, not a name of a value. This also
happens with literal Strings, etc.
Doing ":t g 4" tells ghci to determine the type of the expression "(g
4)". Note that even if you did ":info g T" it will _not_ give you the
info of the expression "(g T)".
Ivan Lazar Miljenovic
Ivan.Miljenovic at gmail.com
More information about the Haskell-Cafe