Hi,
I am a Haskell newbie. I have coded a Regular Expression to Determinate
Finite Automata translator. Algorithm from the Dragon Book.
Would someone eyeball the code and give me suggestions please.
I have not done anything on character classes yet though. And the parsing is
a bit of a hack.
Some comments:
- You can run your code thru HLint, here it gives me 27 suggestions.
- Why don't you derive the Show instance for RE instead of writing it
by yourself?
- Note that
do x
do y
...
is the same as
do x
y
...
- You can parametrize RE as
data RE s p =
The simplest way to make a recogniser out of a RE is to use one of the
available parsing libraries:
module RE where
import Text.ParserCombinators.UU
import Text.ParserCombinators.UU.Examples
data RE = Epsilon | Leaf Char | Selection RE RE | Sequence RE RE | Kleene RE |
Optional RE | End
