From d58ff6bc0b89e714cbba9f82aa41472354e82e2e Mon Sep 17 00:00:00 2001
From: Richard Reeve <git@richardreeve.net>
Date: Tue, 19 Feb 2019 14:46:14 +0000
Subject: [PATCH] Make default getcoords() implementation more precise.

---
 src/DataTypes.jl | 1 +
 src/Interface.jl | 4 +++-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/DataTypes.jl b/src/DataTypes.jl
index 723123e..e7e319a 100644
--- a/src/DataTypes.jl
+++ b/src/DataTypes.jl
@@ -1,3 +1,4 @@
+using Compat: Nothing
 """
     AbstractThings
 
diff --git a/src/Interface.jl b/src/Interface.jl
index 18c7150..1cf40f0 100644
--- a/src/Interface.jl
+++ b/src/Interface.jl
@@ -95,7 +95,9 @@ thingnames(asm::AbstractAssemblage, args...) = thingnames(things(asm), args...)
 # accessing cache
 
 # Methods for AbstractPlaces
-getcoords(plc::AbstractPlaces) = plc # Pure places generate their own fake location data
+getcoords(plc::AbstractPlaces{Nothing}) = plc # Pure places generate their own fake location data
+getcoords(plc::AbstractPlaces{<: AbstractLocationData}) =
+    error("function not defined for $(typeof(plc))")
 coordinates(plc::AbstractPlaces) = error("function not defined for $(typeof(plc))")
 
 # Methods for AbstractGrid