On Fri, 2009-02-13 at 11:40 +0100, Daniel Kraft wrote:
Colin Adams wrote:
If you have two functions that do two different things, then they certainly OUGHT to have different names.
Well, they do "the same thing" but for different arguments; it's like this:
Table is a table of name-value pairs I want to substitute in a tree-like structure using:
substitute :: Table -> Tree -> Tree
For substituting a single name-value pair I want to define this utitlity routine so I don't have to construct a Table all the time in the user code:
substitute :: String -> Value -> Tree -> Tree
You can write it like this: class Substitutable a where substitute :: a -> Tree -> Tree instance Substitutable Table where ... instance Substitutable (String, Value) where ...