Implementation of simple arithmetic expressions from Chapter 3 of Pierce's 'Types and Programming Languages' in Haskell.
The evaluator is a big-step evaluator in Pierce's terminology.
The package provides an executable arith, which presents
the user with a REPL at which arithmetic expressions can be
typed. The sytem prints out a parse tree and the value
of the expression.
It was an experiment for me to see how to implement a little language in Happy and Alex. In particular it uses monadic lexers and parsers in order to gracefully recover from errors.
We also demonstrate the StateT monad transformer and Error monad from the mtl library.
If you have Cabal installed you can build with
cabal build
and run with
cabal run
Otherwise see instructions for building here.
Please send your comments to jyotirmoy@jyotirmoy.net