Made JSON_USE_EXCEPTION's value in config.h a default that can be overridden.
This allows users to override it with their compiler invocation. For example:
g++ -D JSON_USE_EXCEPTION=0 ...
diff --git a/include/json/config.h b/include/json/config.h
index 7609d45..72437c4 100644
--- a/include/json/config.h
+++ b/include/json/config.h
@@ -24,9 +24,11 @@
/// Only has effects if JSON_VALUE_USE_INTERNAL_MAP is defined.
//# define JSON_USE_SIMPLE_INTERNAL_ALLOCATOR 1
-/// If defined, indicates that Json use exception to report invalid type manipulation
-/// instead of C assert macro.
+// If non-zero, the library uses exceptions to report bad input instead of C
+// assertion macros. The default is to use exceptions.
+# ifndef JSON_USE_EXCEPTION
# define JSON_USE_EXCEPTION 1
+# endif
/// If defined, indicates that the source file is amalgated
/// to prevent private header inclusion.