(* Title: Tools/Code/code_haskell.ML
Author: Florian Haftmann, TU Muenchen
Serializer for Haskell.
*)
signature CODE_HASKELL =
sig
val target: string
val setup: theory -> theory
end;
structure Code_Haskell : CODE_HASKELL =
struct
val target = "Haskell";
open Basic_Code_Thingol;
open Code_Printer;
infixr 5 @@;
infixr 5 @|;
(** Haskell serializer **)
fun print_haskell_stmt labelled_name syntax_class syntax_tyco syntax_const
reserved deresolve contr_classparam_typs deriving_show =
let
val deresolve_base = Long_Name.base_name o deresolve;
fun class_name class = case syntax_class class
of NONE => deresolve class
| SOME class => class;
fun print_typcontext tyvars vs = case maps (fn (v, sort) => map (pair v) sort) vs
of [] => []
| constraints => enum "," "(" ")" (
map (fn (v, class) =>
str (class_name class ^ " " ^ lookup_var tyvars v)) constraints)
@@ str " => ";
fun print_typforall tyvars vs = case map fst vs
of [] => []
| vnames => str "forall " :: Pretty.breaks
(map (str o lookup_var tyvars) vnames) @ str "." @@ Pretty.brk 1;
fun print_tyco_expr tyvars fxy (tyco, tys) =
brackify fxy (str tyco :: map (print_typ tyvars BR) tys)
and print_typ tyvars fxy (tycoexpr as tyco `%% tys) = (case syntax_tyco tyco
of NONE => print_tyco_expr tyvars fxy (deresolve tyco, tys)
| SOME (i, print) => print (print_typ tyvars) fxy tys)
| print_typ tyvars fxy (ITyVar v) = (str o lookup_var tyvars) v;
fun print_typdecl tyvars (vs, tycoexpr) =
Pretty.block (print_typcontext tyvars vs @| print_tyco_expr tyvars NOBR tycoexpr);
fun print_typscheme tyvars (vs, ty) =
Pretty.block (print_typforall tyvars vs @ print_typcontext tyvars vs @| print_typ tyvars NOBR ty);
fun print_term tyvars some_thm vars fxy (IConst c) =
print_app tyvars some_thm vars fxy (c, [])
| print_term tyvars some_thm vars fxy (t as (t1 `$ t2)) =
(case Code_Thingol.unfold_const_app t
of SOME app => print_app tyvars some_thm vars fxy app
| _ =>
brackify fxy [
print_term tyvars some_thm vars NOBR t1,
print_term tyvars some_thm vars BR t2
])
| print_term tyvars some_thm vars fxy (IVar NONE) =
str "_"
| print_term tyvars some_thm vars fxy (IVar (SOME v)) =
(str o lookup_var vars) v
| print_term tyvars some_thm vars fxy (t as _ `|=> _) =
let
val (binds, t') = Code_Thingol.unfold_pat_abs t;
val (ps, vars') = fold_map (print_bind tyvars some_thm BR o fst) binds vars;
in brackets (str "\\" :: ps @ str "->" @@ print_term tyvars some_thm vars' NOBR t') end
| print_term tyvars some_thm vars fxy (ICase (cases as (_, t0))) =
(case Code_Thingol.unfold_const_app t0
of SOME (c_ts as ((c, _), _)) => if is_none (syntax_const c)
then print_case tyvars some_thm vars fxy cases
else print_app tyvars some_thm vars fxy c_ts
| NONE => print_case tyvars some_thm vars fxy cases)
and print_app_expr tyvars some_thm vars ((c, (_, function_typs)), ts) = case contr_classparam_typs c
of [] => (str o deresolve) c :: map (print_term tyvars some_thm vars BR) ts
| fingerprint => let
val ts_fingerprint = ts ~~ take (length ts) fingerprint;
val needs_annotation = forall (fn (_, NONE) => true | (t, SOME _) =>
(not o Code_Thingol.locally_monomorphic) t) ts_fingerprint;
fun print_term_anno (t, NONE) _ = print_term tyvars some_thm vars BR t
| print_term_anno (t, SOME _) ty =
brackets [print_term tyvars some_thm vars NOBR t, str "::", print_typ tyvars NOBR ty];
in
if needs_annotation then
(str o deresolve) c :: map2 print_term_anno ts_fingerprint (take (length ts) function_typs)
else (str o deresolve) c :: map (print_term tyvars some_thm vars BR) ts
end
and print_app tyvars = gen_print_app (print_app_expr tyvars) (print_term tyvars) syntax_const
and print_bind tyvars some_thm fxy p = gen_print_bind (print_term tyvars) some_thm fxy p
and print_case tyvars some_thm vars fxy (cases as ((_, [_]), _)) =
let
val (binds, body) = Code_Thingol.unfold_let (ICase cases);
fun print_match ((pat, ty), t) vars =
vars
|> print_bind tyvars some_thm BR pat
|>> (fn p => semicolon [p, str "=", print_term tyvars some_thm vars NOBR t])
val (ps, vars') = fold_map print_match binds vars;
in brackify_block fxy (str "let {")
ps
(concat [str "}", str "in", print_term tyvars some_thm vars' NOBR body])
end
| print_case tyvars some_thm vars fxy (((t, ty), clauses as _ :: _), _) =
let
fun print_select (pat, body) =
let
val (p, vars') = print_bind tyvars some_thm NOBR pat vars;
in semicolon [p, str "->", print_term tyvars some_thm vars' NOBR body] end;
in Pretty.block_enclose
(concat [str "(case", print_term tyvars some_thm vars NOBR t, str "of", str "{"], str "})")
(map print_select clauses)
end
| print_case tyvars some_thm vars fxy ((_, []), _) =
(brackify fxy o Pretty.breaks o map str) ["error", "\"empty case\""];
fun print_stmt (name, Code_Thingol.Fun (_, (((vs, ty), raw_eqs), _))) =
let
val tyvars = intro_vars (map fst vs) reserved;
fun print_err n =
semicolon (
(str o deresolve_base) name
:: map str (replicate n "_")
@ str "="
:: str "error"
@@ (str o ML_Syntax.print_string
o Long_Name.base_name o Long_Name.qualifier) name
);
fun print_eqn ((ts, t), (some_thm, _)) =
let
val consts = fold Code_Thingol.add_constnames (t :: ts) [];
val vars = reserved
|> intro_base_names
(is_none o syntax_const) deresolve consts
|> intro_vars ((fold o Code_Thingol.fold_varnames)
(insert (op =)) ts []);
in
semicolon (
(str o deresolve_base) name
:: map (print_term tyvars some_thm vars BR) ts
@ str "="
@@ print_term tyvars some_thm vars NOBR t
)
end;
in
Pretty.chunks (
semicolon [
(str o suffix " ::" o deresolve_base) name,
print_typscheme tyvars (vs, ty)
]
:: (case filter (snd o snd) raw_eqs
of [] => [print_err ((length o fst o Code_Thingol.unfold_fun) ty)]
| eqs => map print_eqn eqs)
)
end
| print_stmt (name, Code_Thingol.Datatype (_, (vs, []))) =
let
val tyvars = intro_vars (map fst vs) reserved;
in
semicolon [
str "data",
print_typdecl tyvars (vs, (deresolve_base name, map (ITyVar o fst) vs))
]
end
| print_stmt (name, Code_Thingol.Datatype (_, (vs, [((co, _), [ty])]))) =
let
val tyvars = intro_vars (map fst vs) reserved;
in
semicolon (
str "newtype"
:: print_typdecl tyvars (vs, (deresolve_base name, map (ITyVar o fst) vs))
:: str "="
:: (str o deresolve_base) co
:: print_typ tyvars BR ty
:: (if deriving_show name then [str "deriving (Read, Show)"] else [])
)
end
| print_stmt (name, Code_Thingol.Datatype (_, (vs, co :: cos))) =
let
val tyvars = intro_vars (map fst vs) reserved;
fun print_co ((co, _), tys) =
concat (
(str o deresolve_base) co
:: map (print_typ tyvars BR) tys
)
in
semicolon (
str "data"
:: print_typdecl tyvars (vs, (deresolve_base name, map (ITyVar o fst) vs))
:: str "="
:: print_co co
:: map ((fn p => Pretty.block [str "| ", p]) o print_co) cos
@ (if deriving_show name then [str "deriving (Read, Show)"] else [])
)
end
| print_stmt (name, Code_Thingol.Class (_, (v, (super_classes, classparams)))) =
let
val tyvars = intro_vars [v] reserved;
fun print_classparam (classparam, ty) =
semicolon [
(str o deresolve_base) classparam,
str "::",
print_typ tyvars NOBR ty
]
in
Pretty.block_enclose (
Pretty.block [
str "class ",
Pretty.block (print_typcontext tyvars [(v, map fst super_classes)]),
str (deresolve_base name ^ " " ^ lookup_var tyvars v),
str " where {"
],
str "};"
) (map print_classparam classparams)
end
| print_stmt (_, Code_Thingol.Classinst ((class, (tyco, vs)), (_, (classparam_instances, _)))) =
let
val tyvars = intro_vars (map fst vs) reserved;
fun requires_args classparam = case syntax_const classparam
of NONE => 0
| SOME (Code_Printer.Plain_const_syntax _) => 0
| SOME (Code_Printer.Complex_const_syntax (k,_ )) => k;
fun print_classparam_instance ((classparam, const), (thm, _)) =
case requires_args classparam
of 0 => semicolon [
(str o deresolve_base) classparam,
str "=",
print_app tyvars (SOME thm) reserved NOBR (const, [])
]
| k =>
let
val (c, (_, tys)) = const;
val (vs, rhs) = (apfst o map) fst
(Code_Thingol.unfold_abs (Code_Thingol.eta_expand k (const, [])));
val s = if (is_some o syntax_const) c
then NONE else (SOME o Long_Name.base_name o deresolve) c;
val vars = reserved
|> intro_vars (map_filter I (s :: vs));
val lhs = IConst (classparam, (([], []), tys)) `$$ map IVar vs;
(*dictionaries are not relevant at this late stage*)
in
semicolon [
print_term tyvars (SOME thm) vars NOBR lhs,
str "=",
print_term tyvars (SOME thm) vars NOBR rhs
]
end;
in
Pretty.block_enclose (
Pretty.block [
str "instance ",
Pretty.block (print_typcontext tyvars vs),
str (class_name class ^ " "),
print_typ tyvars BR (tyco `%% map (ITyVar o fst) vs),
str " where {"
],
str "};"
) (map print_classparam_instance classparam_instances)
end;
in print_stmt end;
fun haskell_program_of_program labelled_name module_prefix reserved module_alias program =
let
val reserved = Name.make_context reserved;
val mk_name_module = mk_name_module reserved module_prefix module_alias program;
fun add_stmt (name, (stmt, deps)) =
let
val (module_name, base) = dest_name name;
val module_name' = mk_name_module module_name;
val mk_name_stmt = yield_singleton Name.variants;
fun add_fun upper (nsp_fun, nsp_typ) =
let
val (base', nsp_fun') =
mk_name_stmt (if upper then first_upper base else base) nsp_fun
in (base', (nsp_fun', nsp_typ)) end;
fun add_typ (nsp_fun, nsp_typ) =
let
val (base', nsp_typ') = mk_name_stmt (first_upper base) nsp_typ
in (base', (nsp_fun, nsp_typ')) end;
val add_name = case stmt
of Code_Thingol.Fun (_, (_, SOME _)) => pair base
| Code_Thingol.Fun _ => add_fun false
| Code_Thingol.Datatype _ => add_typ
| Code_Thingol.Datatypecons _ => add_fun true
| Code_Thingol.Class _ => add_typ
| Code_Thingol.Classrel _ => pair base
| Code_Thingol.Classparam _ => add_fun false
| Code_Thingol.Classinst _ => pair base;
fun add_stmt' base' = case stmt
of Code_Thingol.Fun (_, (_, SOME _)) =>
I
| Code_Thingol.Datatypecons _ =>
cons (name, (Long_Name.append module_name' base', NONE))
| Code_Thingol.Classrel _ => I
| Code_Thingol.Classparam _ =>
cons (name, (Long_Name.append module_name' base', NONE))
| _ => cons (name, (Long_Name.append module_name' base', SOME stmt));
in
Symtab.map_default (module_name', ([], ([], (reserved, reserved))))
(apfst (fold (insert (op = : string * string -> bool)) deps))
#> `(fn program => add_name ((snd o snd o the o Symtab.lookup program) module_name'))
#-> (fn (base', names) =>
(Symtab.map_entry module_name' o apsnd) (fn (stmts, _) =>
(add_stmt' base' stmts, names)))
end;
val hs_program = fold add_stmt (AList.make (fn name =>
(Graph.get_node program name, Graph.imm_succs program name))
(Graph.strong_conn program |> flat)) Symtab.empty;
fun deresolver name = (fst o the o AList.lookup (op =) ((fst o snd o the
o Symtab.lookup hs_program) ((mk_name_module o fst o dest_name) name))) name
handle Option => error ("Unknown statement name: " ^ labelled_name name);
in (deresolver, hs_program) end;
fun serialize_haskell module_prefix module_name string_classes labelled_name
raw_reserved includes module_alias
syntax_class syntax_tyco syntax_const (code_of_pretty, code_writeln) program
(stmt_names, presentation_stmt_names) width =
let
val reserved = fold (insert (op =) o fst) includes raw_reserved;
val (deresolver, hs_program) = haskell_program_of_program labelled_name
module_prefix reserved module_alias program;
val contr_classparam_typs = Code_Thingol.contr_classparam_typs program;
fun deriving_show tyco =
let
fun deriv _ "fun" = false
| deriv tycos tyco = not (tyco = Code_Thingol.fun_tyco)
andalso (member (op =) tycos tyco
orelse case try (Graph.get_node program) tyco
of SOME (Code_Thingol.Datatype (_, (_, cs))) => forall (deriv' (tyco :: tycos))
(maps snd cs)
| NONE => true)
and deriv' tycos (tyco `%% tys) = deriv tycos tyco
andalso forall (deriv' tycos) tys
| deriv' _ (ITyVar _) = true
in deriv [] tyco end;
val reserved = make_vars reserved;
fun print_stmt qualified = print_haskell_stmt labelled_name
syntax_class syntax_tyco syntax_const reserved
(if qualified then deresolver else Long_Name.base_name o deresolver)
contr_classparam_typs
(if string_classes then deriving_show else K false);
fun print_module name content =
(name, Pretty.chunks2 [
str ("module " ^ name ^ " where {"),
content,
str "}"
]);
fun serialize_module1 (module_name', (deps, (stmts, _))) =
let
val stmt_names = map fst stmts;
val qualified = is_none module_name;
val imports = subtract (op =) stmt_names deps
|> distinct (op =)
|> map_filter (try deresolver)
|> map Long_Name.qualifier
|> distinct (op =);
fun print_import_include (name, _) = str ("import qualified " ^ name ^ ";");
fun print_import_module name = str ((if qualified
then "import qualified "
else "import ") ^ name ^ ";");
val import_ps = map print_import_include includes @ map print_import_module imports
val content = Pretty.chunks2 ((if null import_ps then [] else [Pretty.chunks import_ps])
@ map_filter
(fn (name, (_, SOME stmt)) => SOME (print_stmt qualified (name, stmt))
| (_, (_, NONE)) => NONE) stmts
);
in print_module module_name' content end;
fun serialize_module2 (_, (_, (stmts, _))) = Pretty.chunks2 (map_filter
(fn (name, (_, SOME stmt)) => if null presentation_stmt_names
orelse member (op =) presentation_stmt_names name
then SOME (print_stmt false (name, stmt))
else NONE
| (_, (_, NONE)) => NONE) stmts);
val serialize_module =
if null presentation_stmt_names then serialize_module1 else pair "" o serialize_module2;
fun check_destination destination =
(File.check destination; destination);
fun write_module destination (modlname, content) =
let
val filename = case modlname
of "" => Path.explode "Main.hs"
| _ => (Path.ext "hs" o Path.explode o implode o separate "/"
o Long_Name.explode) modlname;
val pathname = Path.append destination filename;
val _ = File.mkdir_leaf (Path.dir pathname);
in File.write pathname
("{-# OPTIONS_GHC -fglasgow-exts #-}\n\n"
^ code_of_pretty content)
end
in
Code_Target.mk_serialization
(fn width => (fn NONE => K () o map (code_writeln o snd)
| SOME file => K () o map (write_module (check_destination file))))
(fn width => (rpair [] o cat_lines o map (code_of_pretty o snd)))
(map (uncurry print_module) includes
@ map serialize_module (Symtab.dest hs_program))
width
end;
val literals = let
fun char_haskell c =
let
val s = ML_Syntax.print_char c;
in if s = "'" then "\\'" else s end;
fun numeral_haskell k = if k >= 0 then string_of_int k
else Library.enclose "(" ")" (signed_string_of_int k);
in Literals {
literal_char = Library.enclose "'" "'" o char_haskell,
literal_string = quote o translate_string char_haskell,
literal_numeral = numeral_haskell,
literal_positive_numeral = numeral_haskell,
literal_alternative_numeral = numeral_haskell,
literal_naive_numeral = numeral_haskell,
literal_list = enum "," "[" "]",
infix_cons = (5, ":")
} end;
(** optional monad syntax **)
fun pretty_haskell_monad c_bind =
let
fun dest_bind t1 t2 = case Code_Thingol.split_pat_abs t2
of SOME ((pat, ty), t') =>
SOME ((SOME ((pat, ty), true), t1), t')
| NONE => NONE;
fun dest_monad c_bind_name (IConst (c, _) `$ t1 `$ t2) =
if c = c_bind_name then dest_bind t1 t2
else NONE
| dest_monad _ t = case Code_Thingol.split_let t
of SOME (((pat, ty), tbind), t') =>
SOME ((SOME ((pat, ty), false), tbind), t')
| NONE => NONE;
fun implode_monad c_bind_name = Code_Thingol.unfoldr (dest_monad c_bind_name);
fun print_monad print_bind print_term (NONE, t) vars =
(semicolon [print_term vars NOBR t], vars)
| print_monad print_bind print_term (SOME ((bind, _), true), t) vars = vars
|> print_bind NOBR bind
|>> (fn p => semicolon [p, str "<-", print_term vars NOBR t])
| print_monad print_bind print_term (SOME ((bind, _), false), t) vars = vars
|> print_bind NOBR bind
|>> (fn p => semicolon [str "let", str "{", p, str "=", print_term vars NOBR t, str "}"]);
fun pretty _ [c_bind'] print_term thm vars fxy [(t1, _), (t2, _)] = case dest_bind t1 t2
of SOME (bind, t') => let
val (binds, t'') = implode_monad c_bind' t'
val (ps, vars') = fold_map (print_monad (gen_print_bind (K print_term) thm) print_term)
(bind :: binds) vars;
in
(brackify fxy o single o enclose "do { " " }" o Pretty.breaks)
(ps @| print_term vars' NOBR t'')
end
| NONE => brackify_infix (1, L) fxy
(print_term vars (INFX (1, L)) t1, str ">>=", print_term vars (INFX (1, X)) t2)
in (2, ([c_bind], pretty)) end;
fun add_monad target' raw_c_bind thy =
let
val c_bind = Code.read_const thy raw_c_bind;
in if target = target' then
thy
|> Code_Target.add_syntax_const target c_bind
(SOME (Code_Printer.complex_const_syntax (pretty_haskell_monad c_bind)))
else error "Only Haskell target allows for monad syntax" end;
(** Isar setup **)
fun isar_serializer module_name =
Code_Target.parse_args (Scan.option (Args.$$$ "root" -- Args.colon |-- Args.name)
-- Scan.optional (Args.$$$ "string_classes" >> K true) false
>> (fn (module_prefix, string_classes) =>
serialize_haskell module_prefix module_name string_classes));
val _ =
Outer_Syntax.command "code_monad" "define code syntax for monads" Keyword.thy_decl (
Parse.term_group -- Parse.name >> (fn (raw_bind, target) =>
Toplevel.theory (add_monad target raw_bind))
);
val setup =
Code_Target.add_target
(target, { serializer = isar_serializer, literals = literals,
check = { env_var = "EXEC_GHC", make_destination = I,
make_command = fn ghc => fn module_name =>
ghc ^ " -fglasgow-exts -odir build -hidir build -stubdir build -e \"\" " ^ module_name ^ ".hs" } })
#> Code_Target.add_syntax_tyco target "fun" (SOME (2, fn print_typ => fn fxy => fn [ty1, ty2] =>
brackify_infix (1, R) fxy (
print_typ (INFX (1, X)) ty1,
str "->",
print_typ (INFX (1, R)) ty2
)))
#> fold (Code_Target.add_reserved target) [
"hiding", "deriving", "where", "case", "of", "infix", "infixl", "infixr",
"import", "default", "forall", "let", "in", "class", "qualified", "data",
"newtype", "instance", "if", "then", "else", "type", "as", "do", "module"
]
#> fold (Code_Target.add_reserved target) [
"Prelude", "Main", "Bool", "Maybe", "Either", "Ordering", "Char", "String", "Int",
"Integer", "Float", "Double", "Rational", "IO", "Eq", "Ord", "Enum", "Bounded",
"Num", "Real", "Integral", "Fractional", "Floating", "RealFloat", "Monad", "Functor",
"AlreadyExists", "ArithException", "ArrayException", "AssertionFailed", "AsyncException",
"BlockedOnDeadMVar", "Deadlock", "Denormal", "DivideByZero", "DotNetException", "DynException",
"Dynamic", "EOF", "EQ", "EmptyRec", "ErrorCall", "ExitException", "ExitFailure",
"ExitSuccess", "False", "GT", "HeapOverflow",
"IOError", "IOException", "IllegalOperation",
"IndexOutOfBounds", "Just", "Key", "LT", "Left", "LossOfPrecision", "NoMethodError",
"NoSuchThing", "NonTermination", "Nothing", "Obj", "OtherError", "Overflow",
"PatternMatchFail", "PermissionDenied", "ProtocolError", "RecConError", "RecSelError",
"RecUpdError", "ResourceBusy", "ResourceExhausted", "Right", "StackOverflow",
"ThreadKilled", "True", "TyCon", "TypeRep", "UndefinedElement", "Underflow",
"UnsupportedOperation", "UserError", "abs", "absReal", "acos", "acosh", "all",
"and", "any", "appendFile", "asTypeOf", "asciiTab", "asin", "asinh", "atan",
"atan2", "atanh", "basicIORun", "blockIO", "boundedEnumFrom", "boundedEnumFromThen",
"boundedEnumFromThenTo", "boundedEnumFromTo", "boundedPred", "boundedSucc", "break",
"catch", "catchException", "ceiling", "compare", "concat", "concatMap", "const",
"cos", "cosh", "curry", "cycle", "decodeFloat", "denominator", "div", "divMod",
"doubleToRatio", "doubleToRational", "drop", "dropWhile", "either", "elem",
"emptyRec", "encodeFloat", "enumFrom", "enumFromThen", "enumFromThenTo",
"enumFromTo", "error", "even", "exp", "exponent", "fail", "filter", "flip",
"floatDigits", "floatProperFraction", "floatRadix", "floatRange", "floatToRational",
"floor", "fmap", "foldl", "foldl'", "foldl1", "foldr", "foldr1", "fromDouble",
"fromEnum", "fromEnum_0", "fromInt", "fromInteger", "fromIntegral", "fromObj",
"fromRational", "fst", "gcd", "getChar", "getContents", "getLine", "head",
"id", "inRange", "index", "init", "intToRatio", "interact", "ioError", "isAlpha",
"isAlphaNum", "isDenormalized", "isDigit", "isHexDigit", "isIEEE", "isInfinite",
"isLower", "isNaN", "isNegativeZero", "isOctDigit", "isSpace", "isUpper", "iterate", "iterate'",
"last", "lcm", "length", "lex", "lexDigits", "lexLitChar", "lexmatch", "lines", "log",
"logBase", "lookup", "loop", "map", "mapM", "mapM_", "max", "maxBound", "maximum",
"maybe", "min", "minBound", "minimum", "mod", "negate", "nonnull", "not", "notElem",
"null", "numerator", "numericEnumFrom", "numericEnumFromThen", "numericEnumFromThenTo",
"numericEnumFromTo", "odd", "or", "otherwise", "pi", "pred",
"print", "product", "properFraction", "protectEsc", "putChar", "putStr", "putStrLn",
"quot", "quotRem", "range", "rangeSize", "rationalToDouble", "rationalToFloat",
"rationalToRealFloat", "read", "readDec", "readField", "readFieldName", "readFile",
"readFloat", "readHex", "readIO", "readInt", "readList", "readLitChar", "readLn",
"readOct", "readParen", "readSigned", "reads", "readsPrec", "realFloatToRational",
"realToFrac", "recip", "reduce", "rem", "repeat", "replicate", "return", "reverse",
"round", "scaleFloat", "scanl", "scanl1", "scanr", "scanr1", "seq", "sequence",
"sequence_", "show", "showChar", "showException", "showField", "showList",
"showLitChar", "showParen", "showString", "shows", "showsPrec", "significand",
"signum", "signumReal", "sin", "sinh", "snd", "span", "splitAt", "sqrt", "subtract",
"succ", "sum", "tail", "take", "takeWhile", "takeWhile1", "tan", "tanh", "threadToIOResult",
"throw", "toEnum", "toInt", "toInteger", "toObj", "toRational", "truncate", "uncurry",
"undefined", "unlines", "unsafeCoerce", "unsafeIndex", "unsafeRangeSize", "until", "unwords",
"unzip", "unzip3", "userError", "words", "writeFile", "zip", "zip3", "zipWith", "zipWith3"
] (*due to weird handling of ':', we can't do anything else than to import *all* prelude symbols*);
end; (*struct*)