From e1fc9f66900c1ea2b835bafbdc82beb7a10e88ff Mon Sep 17 00:00:00 2001 From: Eelco Dolstra Date: Thu, 2 Apr 2020 19:03:32 +0200 Subject: [PATCH] Improve error message --- src/libexpr/primops/fetchTree.cc | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/libexpr/primops/fetchTree.cc b/src/libexpr/primops/fetchTree.cc index 8a4970726..0838416df 100644 --- a/src/libexpr/primops/fetchTree.cc +++ b/src/libexpr/primops/fetchTree.cc @@ -81,7 +81,7 @@ static void prim_fetchTree(EvalState & state, const Pos & pos, Value * * args, V input = lookupInRegistries(state.store, input).first; if (evalSettings.pureEval && !input->isImmutable()) - throw Error("in pure evaluation mode, 'fetchTree' requires an immutable input"); + throw Error("in pure evaluation mode, 'fetchTree' requires an immutable input, at %s", pos); // FIXME: use fetchOrSubstituteTree auto [tree, input2] = input->fetchTree(state.store);