From 9f7a59af71939e39a6b5bb8fd22c3e74778f3df1 Mon Sep 17 00:00:00 2001
From: Lucas Franceschino <lucas.franceschino@inria.fr>
Date: Mon, 25 May 2020 19:07:38 +0200
Subject: [PATCH] Make `functionArgs` primitive accept primops

(cherry picked from commit b2748c6e99239ff6803ba0da76c362790c8be192)
---
 src/libexpr/primops.cc | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc
index d4c60f870..9a04432e0 100644
--- a/src/libexpr/primops.cc
+++ b/src/libexpr/primops.cc
@@ -1350,6 +1350,10 @@ static void prim_catAttrs(EvalState & state, const Pos & pos, Value * * args, Va
 static void prim_functionArgs(EvalState & state, const Pos & pos, Value * * args, Value & v)
 {
     state.forceValue(*args[0]);
+    if (args[0]->type == tPrimOpApp || args[0]->type == tPrimOp) {
+        state.mkAttrs(v, 0);
+        return;
+    }
     if (args[0]->type != tLambda)
         throw TypeError(format("'functionArgs' requires a function, at %1%") % pos);