Makefile rule to fetch nlohmann/json.hpp

Author: ingydotnet

src/cpp/.gitignore

@@ -0,0 +1 @@
+/ext/

src/cpp/Makefile

@@ -3,6 +3,13 @@ ROOT := ../..
 
 default: help
 
-test: test-tap
+test: ext/nlohmann/json.hpp test-tap
+
+ext/nlohmann/json.hpp:
+	mkdir -p ext/nlohmann
+	curl -s https://raw.githubusercontent.com/nlohmann/json/develop/single_include/nlohmann/json.hpp > $@
+
+clean::
+	rm -fr ext
 
 include ../../.makefile/runtime.mk