From b37f5ae31dc0a0cbfa7e5bbf6b199e7e39c287ac Mon Sep 17 00:00:00 2001
From: Shea Levy <shea@shealevy.com>
Date: Tue, 17 Apr 2018 14:33:12 -0400
Subject: [PATCH] isFunction: True on primops.

Fixes #2073
---
 src/libexpr/primops.cc | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc
index 9e7651da7..57dc7bd12 100644
--- a/src/libexpr/primops.cc
+++ b/src/libexpr/primops.cc
@@ -271,7 +271,18 @@ static void prim_isNull(EvalState & state, const Pos & pos, Value * * args, Valu
 static void prim_isFunction(EvalState & state, const Pos & pos, Value * * args, Value & v)
 {
     state.forceValue(*args[0]);
-    mkBool(v, args[0]->type == tLambda);
+    bool res;
+    switch (args[0]->type) {
+        case tLambda:
+        case tPrimOp:
+        case tPrimOpApp:
+            res = true;
+            break;
+        default:
+            res = false;
+            break;
+    }
+    mkBool(v, res);
 }