cpp ATTENTION: Changed semantics for Payload entry casts to bool

For string values, ONLY the empty string "" maps to false
(previously, "false", "False", and "0" also mapped to false)
For list and map values, zero-element ones now map to false
(previously, any list or map would map to true).

The new semantics are identical to Python behavior for your convenience,
since they were not generically prescribed by the STL anyway.

ipaacalib/cpp/src/ipaaca-payload.cc

@@ -153,7 +153,7 @@ IPAACA_EXPORT template<> bool json_value_cast(const rapidjson::Value& v)
 {
 	if (v.IsString()) {
 		std::string s = v.GetString();
-		return !((s=="")||(s=="false")||(s=="False")||(s=="0"));
+		return !(s==""); // NEW: only empty string maps to false
 	}
 	if (v.IsBool()) return v.GetBool();
 	if (v.IsNull()) return false;
@@ -162,8 +162,10 @@ IPAACA_EXPORT template<> bool json_value_cast(const rapidjson::Value& v)
 	if (v.IsInt64()) return v.GetInt64() != 0;
 	if (v.IsUint64()) return v.GetUint64() != 0;
 	if (v.IsDouble()) return v.GetDouble() != 0.0;
-	// default: assume "pointer-like" semantics (i.e. objects are TRUE)
-	return true;
+	// NEW: empty structures map to false ('Pythonesque' semantics!)
+	if (v.IsArray()) return v.Size() > 0;
+	if (v.IsObject()) return v.MemberCount() > 0;
+	throw NotImplementedError(); // should never be reached anyway
 }
 //}}}