codegen: fix interpreter re-entrance

So multiple successive incremental Evals function correctly.

Also improve the following:
- Apply the same Eval API to vm0 and vm1
- parser: dot diagram display is now synchronous
- codegen: outsource complex code generation for readability
- vm1: Pop take the number of values to pop as operand

1 files changed, 2 insertions, 2 deletions

diff --git a/vm0/vm_test.go b/vm0/vm_test.go
index 0e8896b..dc0829b 100644
--- a/vm0/vm_test.go
+++ b/vm0/vm_test.go
@@ -20,7 +20,7 @@ func TestEval(t *testing.T) {
 	}
 	i.Adot(nodes, os.Getenv("DOT"))
 	for _, n := range nodes {
-		v, err := i.Run(n, "")
-		t.Log(v, err)
+		err := i.Run(n, "")
+		t.Log(err)
 	}
 }