What's the difference between type and data type in Haskell?

haskell typeclass
user997112 picture user997112 · Oct 27, 2011 · Viewed 17.7k times · Source

I'm a little confused as to the difference between a type and a data type in Haskell.

From the literature I have encountered I got the impression they were different concepts.

Answer

Fred Foo picture Fred Foo · Oct 27, 2011

Type and data type refer to exactly the same concept.

The Haskell keywords type and data are different, though: data allows you to introduce a new algebraic data type, while type just makes a type synonym.

See the Haskell wiki for details.

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