evaluate terms when defining them

1 files changed, 11 insertions, 7 deletions

diff --git a/lambda-calcul/haskell/src/Minilang/Lambda.hs b/lambda-calcul/haskell/src/Minilang/Lambda.hs
index d223658..ff636ce 100644
--- a/lambda-calcul/haskell/src/Minilang/Lambda.hs
+++ b/lambda-calcul/haskell/src/Minilang/Lambda.hs
@@ -3,7 +3,7 @@ module Minilang.Lambda where
 import Data.Bifunctor (second)
 import Minilang.Lambda.DeBruijn (eval, eval', fromDeBruijn, toDeBruijn)
 import Minilang.Lambda.Eval (Env, Term)
-import Minilang.Lambda.Infer (Context, TypeError, infer)
+import Minilang.Lambda.Infer (Context, TypeError, extendContext, infer)
 import Minilang.Lambda.Parser (AST (..), desugar)
 import Minilang.Lambda.Unify (Type (..))
 import Minilang.REPL.Types (Language (..))
@@ -38,24 +38,28 @@ loadProgram language env context exprs =
         exprs
 
     runExpr language (Def ident body) env context =
-      let term = desugar body
+      let term = evalInEnv env body
        in case language of
             Typed ->
               case infer term of
                 Left typeError -> Left typeError
                 Right typ ->
-                  Right (Nothing, (ident, term) : env, context)
+                  Right (Nothing, (ident, term) : env, extendContext ident typ context)
             Untyped ->
               Right (Nothing, (ident, term) : env, context)
     runExpr language expr env context =
-      let term = desugar expr
-          env' = second toDeBruijn <$> env
-          v = fromDeBruijn $ eval' env' (toDeBruijn term)
+      let v = evalInEnv env expr
        in case language of
             Typed ->
-              case infer term of
+              case infer v of
                 Left typeError -> Left typeError
                 Right typ ->
                   Right (Just (v, typ), env, context)
             Untyped ->
               Right (Just (v, TyVar "<?>"), env, context)
+
+evalInEnv :: Env -> AST -> Term
+evalInEnv env expr =
+  let term = desugar expr
+      env' = second toDeBruijn <$> env
+   in fromDeBruijn $ eval' env' (toDeBruijn term)