blob: cfa5f6528da3cb3fa2d0a5fdd27131d4d9270969 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
|
module Main where
import Data.Char
import Data.List (isPrefixOf)
import Data.Map (Map, (!))
import qualified Data.Map as M
import System.Environment (getArgs)
import Utils
getFilename [] = error "empty argument list"
getFilename (f : fs) = f
data LWord
= LSymbol String
| LInteger Integer
| LVariable String
deriving (Show)
reprWord (LSymbol a) = a
reprWord (LInteger a) = show a
reprWord (LVariable a) = a
parseWord rawStr
| all isDigit rawStr = LInteger (read rawStr)
| "$" `isPrefixOf` rawStr = LVariable $ tail rawStr
| otherwise = LSymbol rawStr
parseSource source = source $> words .> map parseWord
interpretSource _ _ [] = putStrLn "done"
interpretSource stack dict (word : rest) = do
(newStack, newDict) <- interpretWord stack dict word
interpretSource newStack newDict rest
-- no ops
interpretWord stack dict word@(LInteger value) = pure (word : stack, dict)
interpretWord stack dict word@(LVariable value) = pure (word : stack, dict)
-- variables & printing
interpretWord ((LVariable a) : b : stack) dict word@(LSymbol "!") =
let newDict = M.insert a b dict
in pure (stack, newDict)
interpretWord ((LVariable a) : stack) dict word@(LSymbol "@") =
let lookupWord = dict ! a
in pure (lookupWord : stack, dict)
interpretWord (a : stack) dict word@(LSymbol ".") = do
putStrLn $ reprWord a
pure (stack, dict)
interpretWord ((LVariable a) : stack) dict word@(LSymbol "?") = do
let lookupWord = dict ! a
putStrLn $ reprWord lookupWord
pure (stack, dict)
-- math
interpretWord ((LInteger a) : (LInteger b) : stack) dict word@(LSymbol "+") = pure $ (LInteger (a + b) : stack, dict)
-- error
interpretWord stack _ other = error $ "[error] runtime error at " ++ show other ++ "\nstack at time of error:\n" ++ show stack
main :: IO ()
main = do
args <- getArgs
let filename = getFilename args
putStrLn $ "[info] executing file " ++ filename
source <- readFile filename
putStrLn source
let sourceWoComments = source $> lines .> filter (\line -> not ("--" `isPrefixOf` line)) .> unlines
let parsed = parseSource sourceWoComments
putStrLn $ "[info] parsed words:\n" ++ show parsed
putStrLn "[info] interpreter output:"
interpretSource [] M.empty parsed
|
