--- alreadyEncoded is used in ASSERTs to check for encoded
--- strings. It isn't fail-safe, of course, because, say 'zh' might
--- be encoded or not.
-alreadyEncoded :: String -> Bool
-alreadyEncoded s = all ok s
- where
- ok ' ' = True -- This is a bit of a lie; if we really wanted spaces
- -- in names we'd have to encode them. But we do put
- -- spaces in ccall "occurrences", and we don't want to
- -- reject them here
- ok ch = ISALPHANUM ch
-
-alreadyEncodedFS :: FAST_STRING -> Bool
-alreadyEncodedFS fs = alreadyEncoded (_UNPK_ fs)
-
-encode :: UserString -> EncodedString
-encode cs = case maybe_tuple cs of
- Just n -> 'Z' : show n ++ "T" -- Tuples go to Z2T etc
- Nothing -> go cs
- where
- go [] = []
- go (c:cs) = encode_ch c ++ go cs
-
--- ToDo: Unboxed tuples too, perhaps?
-maybe_tuple ('(' : cs) = check_tuple (0::Int) cs
-maybe_tuple other = Nothing
-
-check_tuple :: Int -> String -> Maybe Int
-check_tuple n (',' : cs) = check_tuple (n+1) cs
-check_tuple n ")" = Just n
-check_tuple n other = Nothing
-
-encodeFS :: UserFS -> EncodedFS
-encodeFS fast_str | all unencodedChar str = fast_str
- | otherwise = _PK_ (encode str)
- where
- str = _UNPK_ fast_str
-
-unencodedChar :: Char -> Bool -- True for chars that don't need encoding
-unencodedChar 'Z' = False
-unencodedChar 'z' = False
-unencodedChar c = ISALPHANUM c
-
-encode_ch :: Char -> EncodedString
-encode_ch c | unencodedChar c = [c] -- Common case first
-
--- Constructors
-encode_ch '(' = "ZL" -- Needed for things like (,), and (->)
-encode_ch ')' = "ZR" -- For symmetry with (
-encode_ch '[' = "ZM"
-encode_ch ']' = "ZN"
-encode_ch ':' = "ZC"
-encode_ch 'Z' = "ZZ"
-
--- Variables
-encode_ch 'z' = "zz"
-encode_ch '&' = "za"
-encode_ch '|' = "zb"
-encode_ch '^' = "zc"
-encode_ch '$' = "zd"
-encode_ch '=' = "ze"
-encode_ch '>' = "zg"
-encode_ch '#' = "zh"
-encode_ch '.' = "zi"
-encode_ch '<' = "zl"
-encode_ch '-' = "zm"
-encode_ch '!' = "zn"
-encode_ch '+' = "zp"
-encode_ch '\'' = "zq"
-encode_ch '\\' = "zr"
-encode_ch '/' = "zs"
-encode_ch '*' = "zt"
-encode_ch '_' = "zu"
-encode_ch '%' = "zv"
-encode_ch c = ['z', 'x', intToDigit hi, intToDigit lo]
- where
- (hi,lo) = ord c `quotRem` 16
-\end{code}
-
-Decode is used for user printing.
-
-\begin{code}
-decodeFS :: FAST_STRING -> FAST_STRING
-decodeFS fs = _PK_ (decode (_UNPK_ fs))
-
-decode :: EncodedString -> UserString
-decode [] = []
-decode ('Z' : rest) = decode_escape rest
-decode ('z' : rest) = decode_escape rest
-decode (c : rest) = c : decode rest
-
-decode_escape :: EncodedString -> UserString
-
-decode_escape ('L' : rest) = '(' : decode rest
-decode_escape ('R' : rest) = ')' : decode rest
-decode_escape ('M' : rest) = '[' : decode rest
-decode_escape ('N' : rest) = ']' : decode rest
-decode_escape ('C' : rest) = ':' : decode rest
-decode_escape ('Z' : rest) = 'Z' : decode rest
-
-decode_escape ('z' : rest) = 'z' : decode rest
-decode_escape ('a' : rest) = '&' : decode rest
-decode_escape ('b' : rest) = '|' : decode rest
-decode_escape ('c' : rest) = '^' : decode rest
-decode_escape ('d' : rest) = '$' : decode rest
-decode_escape ('e' : rest) = '=' : decode rest
-decode_escape ('g' : rest) = '>' : decode rest
-decode_escape ('h' : rest) = '#' : decode rest
-decode_escape ('i' : rest) = '.' : decode rest
-decode_escape ('l' : rest) = '<' : decode rest
-decode_escape ('m' : rest) = '-' : decode rest
-decode_escape ('n' : rest) = '!' : decode rest
-decode_escape ('p' : rest) = '+' : decode rest
-decode_escape ('q' : rest) = '\'' : decode rest
-decode_escape ('r' : rest) = '\\' : decode rest
-decode_escape ('s' : rest) = '/' : decode rest
-decode_escape ('t' : rest) = '*' : decode rest
-decode_escape ('u' : rest) = '_' : decode rest
-decode_escape ('v' : rest) = '%' : decode rest
-decode_escape ('x' : d1 : d2 : rest) = chr (digitToInt d1 * 16 + digitToInt d2) : decode rest
-
--- Tuples are coded as Z23T
-decode_escape (c : rest)
- | isDigit c = go (digitToInt c) rest