X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Fparser%2FLexer.x;h=96660128386e20adcb50a37006fb8aa47704f7e2;hp=43a400471ef139d38950de67616ac3c087de2548;hb=c5b178be60a5a44abd2f4ddf8c399857678326e2;hpb=609940166562b6a5f2ff05fc9d00cf26d531c6dd

diff --git a/compiler/parser/Lexer.x b/compiler/parser/Lexer.x
index 43a4004..9666012 100644
--- a/compiler/parser/Lexer.x
+++ b/compiler/parser/Lexer.x
@@ -56,6 +56,7 @@ module Lexer (
    getLexState, popLexState, pushLexState,
    extension, bangPatEnabled, datatypeContextsEnabled,
    addWarning,
+   incrBracketDepth, incrBracketDepth1, decrBracketDepth, getParserBrakDepth, pushBracketDepth, popBracketDepth,
    lexTokenStream
   ) where
 
@@ -71,6 +72,7 @@ import Module
 import Ctype
 import BasicTypes	( InlineSpec(..), RuleMatchInfo(..), FractionalLit(..) )
 import Util		( readRational )
+import HsSyn (CodeFlavor(..))
 
 import Control.Monad
 import Data.Bits
@@ -326,6 +328,18 @@ $tab+         { warn Opt_WarnTabs (text "Warning: Tab character") }
 }
 
 <0> {
+  "<[" / { ifExtension hetMetEnabled `alexAndPred` notFollowedBySymbol }
+					{ special ITopenBrak }
+  "]>" / { ifExtension hetMetEnabled }  { special ITcloseBrak }
+  "<{" / { ifExtension hetMetEnabled `alexAndPred` notFollowedBySymbol }
+					{ special ITopenBrak1 }
+  "}>" / { ifExtension hetMetEnabled }  { special ITcloseBrak1 }
+  "~~" / { ifExtension hetMetEnabled }  { special ITescape }
+  "%%" / { ifExtension hetMetEnabled }  { special ITdoublePercent }
+  "~~$" / { ifExtension hetMetEnabled }  { special ITescapeDollar }
+}
+
+<0> {
   \? @varid / { ifExtension ipEnabled }	{ skip_one_varid ITdupipvarid }
 }
 
@@ -493,6 +507,7 @@ data Token
   | ITvbar
   | ITlarrow
   | ITrarrow
+  | ITkappa
   | ITat
   | ITtilde
   | ITdarrow
@@ -569,6 +584,15 @@ data Token
   | ITLarrowtail		--  -<<
   | ITRarrowtail		--  >>-
 
+  -- Heterogeneous Metaprogramming extension
+  | ITopenBrak			--  <[
+  | ITcloseBrak			--  ]>
+  | ITopenBrak1			--  <{
+  | ITcloseBrak1		--  }>
+  | ITescape     		--  ~~
+  | ITescapeDollar    		--  ~~$
+  | ITdoublePercent             --  %%
+
   | ITunknown String		-- Used when the lexer can't make sense of it
   | ITeof			-- end of file token
 
@@ -685,6 +709,7 @@ reservedSymsFM = listToUFM $
        ,("|",   ITvbar,     always)
        ,("<-",  ITlarrow,   always)
        ,("->",  ITrarrow,   always)
+       ,("~~>",  ITkappa,   always)
        ,("@",   ITat,       always)
        ,("~",   ITtilde,    always)
        ,("=>",  ITdarrow,   always)
@@ -1530,7 +1555,9 @@ data PState = PState {
         alr_expecting_ocurly :: Maybe ALRLayout,
         -- Have we just had the '}' for a let block? If so, than an 'in'
         -- token doesn't need to close anything:
-        alr_justClosedExplicitLetBlock :: Bool
+        alr_justClosedExplicitLetBlock :: Bool,
+        code_type_bracket_depth       :: [CodeFlavor],
+        code_type_bracket_depth_stack :: [CodeFlavor]
      }
 	-- last_loc and last_len are used when generating error messages,
 	-- and in pushCurrentContext only.  Sigh, if only Happy passed the
@@ -1597,6 +1624,23 @@ setExts f = P $ \s -> POk s{ extsBitmap = f (extsBitmap s) } ()
 setSrcLoc :: RealSrcLoc -> P ()
 setSrcLoc new_loc = P $ \s -> POk s{loc=new_loc} ()
 
+incrBracketDepth :: P ()
+incrBracketDepth = P $ \s -> POk (s{code_type_bracket_depth = KappaFlavor:(code_type_bracket_depth s)}) ()
+incrBracketDepth1 :: P ()
+incrBracketDepth1 = P $ \s -> POk (s{code_type_bracket_depth = LambdaFlavor:(code_type_bracket_depth s)}) ()
+decrBracketDepth :: P ()
+decrBracketDepth = P $ \s -> POk (s{code_type_bracket_depth = tail (code_type_bracket_depth s)}) ()
+pushBracketDepth :: P ()
+pushBracketDepth = P $ \s -> POk (s{code_type_bracket_depth       = tail (code_type_bracket_depth s),
+                                    code_type_bracket_depth_stack = (head (code_type_bracket_depth s)):(code_type_bracket_depth_stack s)
+                                   }) ()
+popBracketDepth :: P ()
+popBracketDepth = P $ \s -> POk (s{code_type_bracket_depth       = (head (code_type_bracket_depth_stack s)):(code_type_bracket_depth s),
+                                   code_type_bracket_depth_stack = tail (code_type_bracket_depth_stack s)
+                                   }) ()
+getParserBrakDepth :: P [CodeFlavor]
+getParserBrakDepth = P $ \s -> POk s (code_type_bracket_depth s)
+
 getSrcLoc :: P RealSrcLoc
 getSrcLoc = P $ \s@(PState{ loc=loc }) -> POk s loc
 
@@ -1807,6 +1851,8 @@ relaxedLayoutBit :: Int
 relaxedLayoutBit = 24
 nondecreasingIndentationBit :: Int
 nondecreasingIndentationBit = 25
+hetMetBit :: Int
+hetMetBit = 31
 
 always :: Int -> Bool
 always           _     = True
@@ -1814,6 +1860,8 @@ parrEnabled :: Int -> Bool
 parrEnabled      flags = testBit flags parrBit
 arrowsEnabled :: Int -> Bool
 arrowsEnabled    flags = testBit flags arrowsBit
+hetMetEnabled :: Int -> Bool
+hetMetEnabled    flags = testBit flags hetMetBit
 thEnabled :: Int -> Bool
 thEnabled        flags = testBit flags thBit
 ipEnabled :: Int -> Bool
@@ -1875,12 +1923,15 @@ mkPState flags buf loc =
       alr_last_loc = alrInitialLoc (fsLit "<no file>"),
       alr_context = [],
       alr_expecting_ocurly = Nothing,
-      alr_justClosedExplicitLetBlock = False
+      alr_justClosedExplicitLetBlock = False,
+      code_type_bracket_depth = [],
+      code_type_bracket_depth_stack = []
     }
     where
       bitmap =     ffiBit            `setBitIf` xopt Opt_ForeignFunctionInterface flags
                .|. parrBit           `setBitIf` xopt Opt_ParallelArrays  flags
                .|. arrowsBit         `setBitIf` xopt Opt_Arrows          flags
+	       .|. hetMetBit         `setBitIf` xopt Opt_ModalTypes      flags
                .|. thBit             `setBitIf` xopt Opt_TemplateHaskell flags
                .|. qqBit             `setBitIf` xopt Opt_QuasiQuotes     flags
                .|. ipBit             `setBitIf` xopt Opt_ImplicitParams  flags