Wrap static _##ENUM_TYPENAME##_constants_string var in `_Pragma("cl…

…ang diagnostic ignored \"-Wunused-value\"")` to suppress "Unused variable" warnings as pointed out in #3.

Pretty sure these warnings didn't show up with the version of Xcode/clang that I wrote JREnum with.

Anyway, this is kinda academic since a couple of versions back `_Pragma("clang diagnostic ignored \"-Wunused-value\"")` stopped working. I'm putting this in here anyway hoping it starts working again in a future version of clang.

JREnum.h

@@ -21,7 +21,10 @@
     extern NSDictionary* ENUM_TYPENAME##ByLabel();  \
     extern NSString* ENUM_TYPENAME##ToString(int enumValue);    \
     extern BOOL ENUM_TYPENAME##FromString(NSString *enumLabel, ENUM_TYPENAME *enumValue);   \
-    static NSString *_##ENUM_TYPENAME##_constants_string = @"" #ENUM_CONSTANTS;
+    _Pragma("clang diagnostic push") \
+    _Pragma("clang diagnostic ignored \"-Wunused-value\"") \
+    static NSString *_##ENUM_TYPENAME##_constants_string = @"" #ENUM_CONSTANTS; \
+    _Pragma("clang diagnostic pop")
 
 #define JREnumDefine(ENUM_TYPENAME) \
     _JREnum_GenerateImplementation(ENUM_TYPENAME)