diff options
Diffstat (limited to 'src/PGF')
| -rw-r--r-- | src/PGF/Expr.hs | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/src/PGF/Expr.hs b/src/PGF/Expr.hs index bddbc84d4..cf0cb79aa 100644 --- a/src/PGF/Expr.hs +++ b/src/PGF/Expr.hs @@ -5,6 +5,7 @@ module PGF.Expr(Tree, BindType(..), Expr(..), Literal(..), Patt(..), Equation(.. mkStr, unStr,
mkInt, unInt,
mkDouble, unDouble,
+ mkMeta, isMeta,
normalForm,
@@ -132,6 +133,15 @@ unDouble :: Expr -> Maybe Double unDouble (ELit (LFlt f)) = Just f
unDouble _ = Nothing
+-- | Constructs an expression which is meta variable
+mkMeta :: Expr
+mkMeta = EMeta 0
+
+-- | Checks whether an expression is a meta variable
+isMeta :: Expr -> Bool
+isMeta (EMeta _) = True
+isMeta _ = False
+
-----------------------------------------------------
-- Parsing
-----------------------------------------------------
|