Re: [Haskell-cafe] Design of a DSL in Haskell

In Haskell, shallow DSLs generate values - deep DSLs generate structures (typically abstract syntax trees), the structure can subsequently be used to generate a value (or a C program, or a HTML page, etc.). See Andy Gill and colleagues "Types and Type Families for Hardware Simulation and Synthesis, The Internals and Externals of Kansas Lava" for a fuller definition. http://www.ittc.ku.edu/csdl/fpg/sites/default/files/Gill-10-TypesKansasLava.... Other communities may have their own definitions. On 4 December 2012 10:01, Kim-Ee Yeoh wrote:

On Tue, Dec 4, 2012 at 4:53 PM, Joerg Fritsch wrote:

...

is a shallow embedded DSL == an internal DSL and a deeply embedded DSL == an external DSL or the other way around?

Roughly speaking, yes. But a deep DSL doesn't mean you've got to have a parser << tokenizer << IO input. You can get a deep DSL merely from the free monad construction.

-- Kim-Ee