diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/Helper.hs | 8 | ||||
| -rw-r--r-- | src/Parser.hs | 3 |
2 files changed, 10 insertions, 1 deletions
diff --git a/src/Helper.hs b/src/Helper.hs index 2b2e31c..f760597 100644 --- a/src/Helper.hs +++ b/src/Helper.hs @@ -328,6 +328,14 @@ decimalToUnary n | n < 0 = decimalToUnary 0 gen 0 = Bruijn 0 gen n' = Application (Bruijn 1) (gen (n' - 1)) +-- Decimal to De Bruijn encoding +decimalToDeBruijn :: Integer -> Expression +decimalToDeBruijn n | n < 0 = decimalToDeBruijn 0 + | otherwise = gen n + where + gen 0 = Abstraction $ Bruijn $ fromInteger n + gen n' = Abstraction $ gen (n' - 1) + unaryToDecimal :: Expression -> Maybe String unaryToDecimal e = do res <- resolve e diff --git a/src/Parser.hs b/src/Parser.hs index 12214a0..470c18f 100644 --- a/src/Parser.hs +++ b/src/Parser.hs @@ -118,13 +118,14 @@ parseNumeral :: Parser Expression parseNumeral = do _ <- string "(" <?> "number start" num <- number <?> "signed number" - base <- try (oneOf "ubt") <|> return 't' + base <- try (oneOf "dubt") <|> return 't' _ <- string ")" <?> "number end" pure $ f base num where f 't' = decimalToTernary f 'b' = decimalToBinary f 'u' = decimalToUnary + f 'd' = decimalToDeBruijn f _ = invalidProgramState sign :: Parser (Integer -> Integer) sign = (char '-' >> return negate) <|> (char '+' >> return id) |