Fixed Issue 7: GenericValue& operator[](const Ch* name) - bug if key not found

Makes GenericValue::FindMember() public.
Added array element and object member iteration APIs in examples.

git-svn-id: https://rapidjson.googlecode.com/svn/trunk@83 c5894555-1306-4e8d-425f-1f6f381ee07c

example/tutorial/tutorial.cpp

@@ -41,6 +41,12 @@ int main(int argc, char* argv[]) {
 	assert(document["hello"].IsString());
 	printf("hello = %s\n", document["hello"].GetString());
 
+	// Since version 0.2, you can use single lookup to check the existing of member and its value:
+	Value::Member* hello = document.FindMember("hello");
+	assert(hello != 0);
+	assert(hello->value.IsString());
+	assert(strcmp("world", hello->value.GetString()) == 0);
+
 	assert(document["t"].IsBool());		// JSON true/false are bool. Can also uses more specific function IsTrue().
 	printf("t = %s\n", document["t"].GetBool() ? "true" : "false");
 
@@ -67,8 +73,20 @@ int main(int argc, char* argv[]) {
 		//int x = a[0].GetInt();					// Error: operator[ is ambiguous, as 0 also mean a null pointer of const char* type.
 		int y = a[SizeType(0)].GetInt();			// Cast to SizeType will work.
 		int z = a[0u].GetInt();						// This works too.
+
+		// Iterating array with iterators
+		printf("a = ");
+		for (Value::ConstValueIterator itr = a.Begin(); itr != a.End(); ++itr)
+			printf("%d ", itr->GetInt());
+		printf("\n");
 	}
 
+	// Iterating object members
+	static const char* kTypeNames[] = { "Null", "False", "True", "Object", "Array", "String", "Number" };
+	for (Value::ConstMemberIterator itr = document.MemberBegin(); itr != document.MemberEnd(); ++itr)
+		printf("Type of member %s is %s\n", itr->name.GetString(), kTypeNames[itr->value.GetType()]);
+
+	////////////////////////////////////////////////////////////////////////////
 	// 3. Modify values in document.
 
 	// Change i to a bigger number

include/rapidjson/document.h

@@ -227,11 +227,18 @@ public:
 	//! Set this value as an empty object.
 	GenericValue& SetObject() { this->~GenericValue(); new (this) GenericValue(kObjectType); return *this; }
 
-	//! Get the value associated with the object's name.
+	//! Get the value associated with the name.
+	/*!
+		\note In version 0.1x, if the member is not found, this function returns a null value. This makes issue 7.
+		Since 0.2, if the name is not correct, it will assert.
+		If user is unsure whether a member exists, user should use HasMember() first.
+		A better approach is to use the now public FindMember().
+	*/
 	GenericValue& operator[](const Ch* name) {
 		if (Member* member = FindMember(name))
 			return member->value;
 		else {
+			RAPIDJSON_ASSERT(false);	// see above note
 			static GenericValue NullValue;
 			return NullValue;
 		}
@@ -245,8 +252,28 @@ public:
 	MemberIterator MemberEnd()				{ RAPIDJSON_ASSERT(IsObject()); return data_.o.members + data_.o.size; }
 
 	//! Check whether a member exists in the object.
+	/*!
+		\note It is better to use FindMember() directly if you need the obtain the value as well.
+	*/
 	bool HasMember(const Ch* name) const { return FindMember(name) != 0; }
 
+	//! Find member by name.
+	/*!
+		\return Return the member if exists. Otherwise returns null pointer.
+	*/
+	Member* FindMember(const Ch* name) {
+		RAPIDJSON_ASSERT(name);
+		RAPIDJSON_ASSERT(IsObject());
+
+		Object& o = data_.o;
+		for (Member* member = o.members; member != data_.o.members + data_.o.size; ++member)
+			if (name[member->name.data_.s.length] == '\0' && memcmp(member->name.data_.s.str, name, member->name.data_.s.length * sizeof(Ch)) == 0)
+				return member;
+
+		return 0;
+	}
+	const Member* FindMember(const Ch* name) const { return const_cast<GenericValue&>(*this).FindMember(name); }
+
 	//! Add a member (name-value pair) to the object.
 	/*! \param name A string value as name of member.
 		\param value Value of any type.
@@ -613,20 +640,6 @@ private:
 		Array a;
 	};	// 12 bytes in 32-bit mode, 16 bytes in 64-bit mode
 
-	//! Find member by name.
-	Member* FindMember(const Ch* name) {
-		RAPIDJSON_ASSERT(name);
-		RAPIDJSON_ASSERT(IsObject());
-
-		Object& o = data_.o;
-		for (Member* member = o.members; member != data_.o.members + data_.o.size; ++member)
-			if (name[member->name.data_.s.length] == '\0' && memcmp(member->name.data_.s.str, name, member->name.data_.s.length * sizeof(Ch)) == 0)
-				return member;
-
-		return 0;
-	}
-	const Member* FindMember(const Ch* name) const { return const_cast<GenericValue&>(*this).FindMember(name); }
-
 	// Initialize this value as array with initial data, without calling destructor.
 	void SetArrayRaw(GenericValue* values, SizeType count, Allocator& alloctaor) {
 		flags_ = kArrayFlag;