[project @ 1996-01-08 20:28:12 by partain]

[ghc-hetmet.git] / ghc / compiler / abstractSyn / HsLit.lhs

diff --git a/ghc/compiler/abstractSyn/HsLit.lhs b/ghc/compiler/abstractSyn/HsLit.lhs
new file mode 100644 (file)
index 0000000..bf5ae19
--- /dev/null
+++ b/ghc/compiler/abstractSyn/HsLit.lhs
@@ -0,0 +1,76 @@
+%
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1994
+%
+\section[HsLit]{Abstract syntax: source-language literals}
+
+\begin{code}
+#include "HsVersions.h"
+
+module HsLit where
+
+import AbsPrel         ( PrimKind )
+import Outputable
+import Pretty
+import Util
+\end{code}
+
+\begin{code}
+data Literal
+  = CharLit        Char        -- characters
+  | CharPrimLit            Char        -- unboxed char literals
+  | StringLit      FAST_STRING -- strings
+  | StringPrimLit   FAST_STRING        -- packed string
+
+  | IntLit         Integer     -- integer-looking literals
+  | FracLit        Rational    -- frac-looking literals
+       -- Up through dict-simplification, IntLit and FracLit simply
+       -- mean the literal was integral- or fractional-looking; i.e.,
+       -- whether it had an explicit decimal-point in it.  *After*
+       -- dict-simplification, they mean (boxed) "Integer" and
+       -- "Rational" [Ratio Integer], respectively.
+
+       -- Dict-simplification tries to replace such lits w/ more
+       -- specific ones, using the unboxed variants that follow...
+  | LitLitLitIn            FAST_STRING -- to pass ``literal literals'' through to C
+                               -- also: "overloaded" type; but
+                               -- must resolve to boxed-primitive!
+                               -- (WDP 94/10)
+  | LitLitLit      FAST_STRING
+                   UniType     -- and now we know the type
+                               -- Must be a boxed-primitive type
+
+  | IntPrimLit     Integer     -- unboxed Int literals
+#if __GLASGOW_HASKELL__ <= 22
+  | FloatPrimLit    Double     -- unboxed Float literals
+  | DoublePrimLit   Double     -- unboxed Double literals
+#else
+  | FloatPrimLit    Rational   -- unboxed Float literals
+  | DoublePrimLit   Rational   -- unboxed Double literals
+#endif
+\end{code}
+
+\begin{code}
+negLiteral (IntLit  i) = IntLit  (-i)
+negLiteral (FracLit f) = FracLit (-f)
+\end{code}
+
+\begin{code}
+instance Outputable Literal where
+    ppr sty (CharLit c)                = ppStr (show c)
+    ppr sty (CharPrimLit c)    = ppBeside (ppStr (show c)) (ppChar '#')
+    ppr sty (StringLit s)      = ppStr (show s)
+    ppr sty (StringPrimLit s)  = ppBeside (ppStr (show s)) (ppChar '#')
+    ppr sty (IntLit i)         = ppInteger i
+#if __GLASGOW_HASKELL__ <= 22
+    ppr sty (FracLit f)                = ppDouble (fromRational f) -- ToDo: better??
+    ppr sty (FloatPrimLit f)   = ppBeside (ppDouble f) (ppChar '#')
+    ppr sty (DoublePrimLit d)  = ppBeside (ppDouble d) (ppStr "##")
+#else
+    ppr sty (FracLit f)                = ppRational f
+    ppr sty (FloatPrimLit f)   = ppBeside (ppRational f) (ppChar '#')
+    ppr sty (DoublePrimLit d)  = ppBeside (ppRational d) (ppStr "##")
+#endif
+    ppr sty (IntPrimLit i)     = ppBeside (ppInteger i) (ppChar '#')
+    ppr sty (LitLitLitIn s)    = ppBesides [ppStr "``", ppPStr s, ppStr "''"]
+    ppr sty (LitLitLit s k)    = ppBesides [ppStr "``", ppPStr s, ppStr "''"]
+\end{code}