blob: 62eff14a185a0d20e12a6948e62838ac8d4efaac (
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
|
module Parser (
parse,
) where
import qualified Data.Map as M
import qualified Data.List as L
import Control.Monad.Except
import Text.Regex.TDFA
import Utils
validateBalance :: [String] -> [AST] -> LContext [AST]
validateBalance allowed asts = do
when (ASTSymbol "(" `elem` asts && "(" `notElem` allowed)
$ throwL "unbalanced function call"
when (ASTSymbol "[" `elem` asts && "[" `notElem` allowed)
$ throwL "unbalanced vector"
when (ASTSymbol "{" `elem` asts && "{" `notElem` allowed)
$ throwL "unbalanced hash map"
return asts
parseToken :: String -> AST
parseToken token
| isInteger token = ASTInteger (read token)
| isDouble token = ASTDouble (read token)
| isString token = ASTString $ removeQuotes token
| isBoolean token = ASTBoolean $ asBoolean token
| otherwise = ASTSymbol token
where
integerRegex = "^-?[[:digit:]]+$"
isInteger :: String -> Bool
isInteger t = t =~ integerRegex
doubleRegex = "^-?[[:digit:]]+(\\.[[:digit:]]+)?$"
isDouble :: String -> Bool
isDouble t = t =~ doubleRegex
isString t = "\"" `L.isPrefixOf` t
removeQuotes s = drop 1 s $> take (length s - 2)
isBoolean t = t `elem` ["true", "false"]
asBoolean t = if t == "true" then True else False
_parse :: [AST] -> [String] -> LContext [AST]
_parse acc' [] = do
acc <- validateBalance [] acc'
return $ reverse acc
_parse acc (")":rest) = do
let children' = takeWhile (/= ASTSymbol "(") acc
children <- validateBalance ["("] children'
let fnCall = ASTFunctionCall (reverse children)
let newAcc = fnCall : drop (length children + 1) acc
_parse newAcc rest
_parse acc ("]":rest) = do
let children' = takeWhile (/= ASTSymbol "[") acc
children <- validateBalance ["["] children'
let vec = ASTVector (reverse children)
let newAcc = vec : drop (length children + 1) acc
_parse newAcc rest
_parse acc ("}":rest) = do
let children' = takeWhile (/= ASTSymbol "{") acc
children <- validateBalance ["{"] children'
pairs <- asPairsM $ reverse children
let vec = ASTHashMap (M.fromList pairs)
let newAcc = vec : drop (length children + 1) acc
_parse newAcc rest
_parse acc (token:rest) =
_parse (parseToken token : acc) rest
parse :: [String] -> LContext [AST]
parse = _parse []
|
