34 lines
897 B
Plaintext
34 lines
897 B
Plaintext
|
data Token : Set where
|
||
|
|
Digit : Nat → Token
|
||
|
|
Delim : Char → Token
|
||
|
|
Oper : Char → Token
|
||
|
|
Term : Token
|
||
|
|
|
||
|
|
parseChar : Char → Token
|
||
|
|
parseChar '0' = Digit 0
|
||
|
|
parseChar '1' = Digit 1
|
||
|
|
parseChar '2' = Digit 2
|
||
|
|
parseChar '3' = Digit 3
|
||
|
|
parseChar '4' = Digit 4
|
||
|
|
parseChar '5' = Digit 5
|
||
|
|
parseChar '6' = Digit 6
|
||
|
|
parseChar '7' = Digit 7
|
||
|
|
parseChar '8' = Digit 8
|
||
|
|
parseChar '9' = Digit 9
|
||
|
|
parseChar ',' = Delim ','
|
||
|
|
parseChar '=' = Oper '='
|
||
|
|
parseChar '+' = Oper '+'
|
||
|
|
parseChar _ = Term
|
||
|
|
|
||
|
|
parseList : Nat → List Char → List Nat
|
||
|
|
parseList a [] = a ∷ []
|
||
|
|
parseList a (x ∷ xs) with parseChar x
|
||
|
|
... | Digit n = parseList ((a * 10) + n) xs
|
||
|
|
... | Delim s = a ∷ parseList 0 xs
|
||
|
|
... | Oper o = [] -- ignore for now
|
||
|
|
... | Term = []
|
||
|
|
|
||
|
|
parseExpr : String → List Nat
|
||
|
|
parseExpr "" = []
|
||
|
|
parseExpr x = parseList 0 (primStringToList x)
|