diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc
index b2a8651d9..03329645f 100644
--- a/src/libexpr/eval.cc
+++ b/src/libexpr/eval.cc
@@ -747,14 +747,6 @@ LocalNoInlineNoReturn(void throwEvalError(const Pos & p1, const char * s, const
     });
 }
 
-LocalNoInlineNoReturn(void throwTypeError(const Pos & pos, const char * s))
-{
-    throw TypeError({
-        .msg = hintfmt(s),
-        .errPos = pos
-    });
-}
-
 LocalNoInlineNoReturn(void throwTypeError(const Pos & pos, const char * s, const ExprLambda & fun, const Symbol & s2))
 {
     throw TypeError({
@@ -763,11 +755,6 @@ LocalNoInlineNoReturn(void throwTypeError(const Pos & pos, const char * s, const
     });
 }
 
-//LocalNoInlineNoReturn(void throwTypeError(const char * s, const Value & v))
-//{
-//    throw TypeError(s, showType(v));
-//}
-
 LocalNoInlineNoReturn(void throwTypeError(const Pos & pos, const char * s, const Value & v))
 {
     throw AssertionError({
@@ -1371,7 +1358,7 @@ void EvalState::callFunction(Value & fun, size_t nrArgs, Value * * args, Value &
                 for (auto & i : lambda.formals->formals) {
                     auto j = args[0]->attrs->get(i.name);
                     if (!j) {
-                        if (!i.def) throwTypeError(pos, "%1% called without required argument '%2%'",
+                        if (!i.def) throwTypeError(pos, "Function %1% called without required argument '%2%'",
                             lambda, i.name);
                         env2.values[displ++] = i.def->maybeThunk(*this, env2);
                     } else {
@@ -1387,7 +1374,7 @@ void EvalState::callFunction(Value & fun, size_t nrArgs, Value * * args, Value &
                        user. */
                     for (auto & i : *args[0]->attrs)
                         if (!lambda.formals->has(i.name))
-                            throwTypeError(pos, "%1% called with unexpected argument '%2%'", lambda, i.name);
+                            throwTypeError(pos, "Function %1% called with unexpected argument '%2%'", lambda, i.name);
                     abort(); // can't happen
                 }
             }
@@ -2059,7 +2046,7 @@ Path EvalState::coerceToPath(const Pos & pos, Value & v, PathSet & context, cons
 
 StorePath EvalState::coerceToStorePath(const Pos & pos, Value & v, PathSet & context, const std::string & errorCtx)
 {
-    auto path = coerceToString(pos, v, context, false, false, errorCtx).toOwned();
+    auto path = coerceToString(pos, v, context, false, false, true, errorCtx).toOwned();
     if (auto storePath = store->maybeParseStorePath(path))
         return *storePath;
     throw EvalError({
diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc
index b56293c30..a72d0f12a 100644
--- a/src/libexpr/primops.cc
+++ b/src/libexpr/primops.cc
@@ -683,12 +683,12 @@ static void prim_genericClosure(EvalState & state, const Pos & pos, Value * * ar
         res.push_back(e);
 
         /* Call the `operator' function with `e' as argument. */
-        Value call;
-        call.mkApp(op->value, e);
-        state.forceList(call, pos, "While evaluating the return value of the `operator` passed to builtins.genericClosure");
+        Value res;
+        state.callFunction(*op->value, 1, &e, res, *op->pos);
+        state.forceList(res, pos, "While evaluating the return value of the `operator` passed to builtins.genericClosure");
 
         /* Add the values returned by the operator to the work set. */
-        for (auto elem : call.listItems()) {
+        for (auto elem : res.listItems()) {
             state.forceValue(*elem, pos);
             workSet.push_back(elem);
         }
@@ -2033,7 +2033,7 @@ static void prim_path(EvalState & state, const Pos & pos, Value * * args, Value
         else if (attr.name == state.sName)
             name = state.forceStringNoCtx(*attr.value, *attr.pos, "while evaluating the `name` attribute passed to builtins.path");
         else if (n == "filter")
-            state.forceFunction(filterFun = *attr.value, *attr.pos, "While evaluating the `filter` parameter passed to builtins.path");
+            state.forceFunction(*(filterFun = attr.value), *attr.pos, "While evaluating the `filter` parameter passed to builtins.path");
         else if (n == "recursive")
             method = FileIngestionMethod { state.forceBool(*attr.value, *attr.pos, "While evaluating the `recursive` attribute passed to builtins.path") };
         else if (n == "sha256")