restored gfcc example (GF C compiler)

examples/gfcc/ImperC.gf

@@ -0,0 +1,56 @@
+--# -path=.:../../lib/prelude
+concrete ImperC of Imper = open ResImper in {
+  flags lexer=codevars ; unlexer=code ; startcat=Program ;
+
+  lincat
+    Exp = PrecExp ; 
+    Typ = {s,s2 : Str} ;
+    Rec = {s,s2,s3 : Str} ;
+
+  lin
+    Empty = ss [] ;
+    FunctNil val stm cont = ss (
+      val.s ++ cont.$0 ++ paren [] ++ "{" ++ 
+      stm.s ++ "}" ++ ";" ++ cont.s) ;
+    Funct args val rec = ss (
+      val.s ++ rec.$0 ++ paren rec.s2 ++ "{" ++ 
+      rec.s ++ "}" ++ ";" ++ rec.s3) ;
+
+    RecOne typ stm prg = stm ** {
+      s2 = typ.s ++ stm.$0 ;
+      s3 = prg.s
+      } ;
+    RecCons typ _ body prg = {
+      s  = body.s ; 
+      s2 = typ.s ++ body.$0 ++ "," ++ body.s2 ;
+      s3 = prg.s
+      } ;
+
+    Decl  typ cont = continues (typ.s ++ cont.$0) cont ;
+    Assign _ x exp = continues (x.s ++ "=" ++ exp.s) ;
+    While exp loop = continue  ("while" ++ paren exp.s ++ loop.s) ;
+    IfElse exp t f = continue  ("if" ++ paren exp.s ++ t.s ++ "else" ++ f.s) ;
+    Block stm      = continue  ("{" ++ stm.s ++ "}") ;
+    Printf t e     = continues ("printf" ++ paren (t.s2 ++ "," ++ e.s)) ;
+    Return _ exp   = statement ("return" ++ exp.s) ;
+    Returnv        = statement "return" ;
+    End            = ss [] ;
+ 
+    EVar  _ x  = constant x.s ;
+    EInt    n  = constant n.s ;
+    EFloat a b = constant (a.s ++ "." ++ b.s) ;
+    EMul _ _   = infixL 3 "*" ;
+    EAdd _ _   = infixL 2 "+" ;
+    ESub _ _   = infixL 2 "-" ;
+    ELt _ _    = infixN 1 "<" ;
+
+    EAppNil val f = constant (f.s ++ paren []) ;
+    EApp args val f exps = constant (f.s ++ paren exps.s) ;
+
+    TInt    = {s = "int" ; s2 = "\"%d\""} ; 
+    TFloat  = {s = "float" ; s2 = "\"%f\""} ;
+    NilTyp  = ss [] ;
+    ConsTyp = cc2 ;
+    OneExp _ e = e ;
+    ConsExp _ _ e es = ss (e.s ++ "," ++ es.s) ;
+}