Add ContExpression syntax tree.

This is for expressions which must be calculatable at compile time.

1 files changed, 6 insertions, 3 deletions

diff --git a/src/Language/Fiddle/Parser.hs b/src/Language/Fiddle/Parser.hs
index ebbd51b..dea2dd5 100644
--- a/src/Language/Fiddle/Parser.hs
+++ b/src/Language/Fiddle/Parser.hs
@@ -146,7 +146,7 @@ fiddleDeclP = do
           <$> name
           <*> defer body packageBodyP
       KWUsing -> UsingDecl Witness <$> name
-      KWLocation -> LocationDecl noQMd <$> ident <*> (tok TokEq >> expressionP)
+      KWLocation -> LocationDecl noQMd <$> ident <*> (tok TokEq >> constExpressionP)
       KWBits -> BitsDecl noQMd <$> ident <*> (tok TokColon >> bitTypeP)
       KWImport -> ImportDecl <$> importStatementP
       KWType ->
@@ -176,7 +176,7 @@ objTypeP = do
     recur =
       ( do
           withMeta $ do
-            expr <- tok TokLBracket *> expressionP <* tok TokRBracket
+            expr <- tok TokLBracket *> constExpressionP <* tok TokRBracket
             recur' <- recur
             return (\met base -> recur' (ArrayObjType base expr met))
       )
@@ -274,7 +274,7 @@ registerBitsTypeRefP = do
     recurP =
       ( do
           withMeta $ do
-            expr <- tok TokLBracket *> expressionP <* tok TokRBracket
+            expr <- tok TokLBracket *> constExpressionP <* tok TokRBracket
             recur' <- recurP
             return (\met base -> recur' (RegisterBitsArray base expr met))
       )
@@ -311,6 +311,9 @@ enumConstantDeclP =
     (tok KWReserved >> EnumConstantReserved <$> (tok TokEq >> expressionP))
       <|> (EnumConstantDecl <$> ident <*> (tok TokEq >> expressionP))
 
+constExpressionP :: Pa (ConstExpression u)
+constExpressionP = withMeta $ ConstExpression . RightV <$> expressionP
+
 expressionP :: Pa (Expression u)
 expressionP =
   withMeta $