A C++ template library for embedded applications
MIT licensed
Designed and
maintained by
John Wellbelove

message_packet


A container for more than one type of message.
The messages must have been derived from etl::imessage.

The messages types that the packet may contain are listed as template parameters.
e.g. etl::message_packet<Message1, Message2, Message3>

From 20.40.0 message types are not rquired to have a virtual destructor.

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message_packet()
Default constructs a message packet.
is_valid() returns false.
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explicit message_packet(const etl::imessage&)
Constructs a message packet from an etl::imessage reference.
Asserts an etl::unhandled_message_exception error if the parameter is not one listed in the template parameter list.
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explicit message_packet(etl::imessage&&) C++11
Move constructs a message packet from an etl::imessage rvalue reference.
Emits an etl::unhandled_message_exception error if the parameter is not one listed in the template parameter list.
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20.22.0
template <typename TMessage>
explicit message_packet(const TMessage&)
Constructs a message packet from a TMessage reference.
Emits a compile time static assert if the parameter is not one listed in the template parameter list.
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20.22.0
template <typename TMessage>
explicit message_packet(TMessage&&) C++11
Move constructs a message packet from a TMessage rvalue reference.
Emits a compile time static assert if the parameter is not one listed in the template parameter list.
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message_packet(const message_packet&)
Constructs a message packet from an message_packet reference.
Emits an etl::unhandled_message_exception error if the parameter is not one listed in the template parameter list.
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message_packet(message_packet&&)
Move constructs a message packet from an message_packet rvalue reference.
Emits an etl::unhandled_message_exception if the parameter is not one listed in the template parameter list.
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message_packet& operator =(const message_packet&)
Assigns a message packet from an message_packet reference.
Emits an etl::unhandled_message_exception error if the parameter is not one listed in the template parameter list.
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message_packet& operator =(message_packet&&)
Move assigns a message packet from an message_packet rvalue reference.
Emits an etl::unhandled_message_exception error if the parameter is not one listed in the template parameter list.
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etl::imessage& get()
const etl::imessage& get() const
Returns a reference to an etl::imessage
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bool is_valid() const
Returns true if the packet contains a valid message, otherwise false.
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Constants


SIZE      The size of the largest message.
ALIGNMENT The largest message alignment.

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Example


enum
{
  MESSAGE1,
  MESSAGE2,
  MESSAGE3
};

struct Message1 : public etl::message<MESSAGE1>
{
};

struct Message2 : public etl::message<MESSAGE2>
{
};

struct Message3 : public etl::message<MESSAGE3>
{
};

using Packet = etl::message_packet<Message1, Message2>

Message1 message1;
Message2 message2;
Message3 message3;

Packet packet1(message1);
Packet packet2(message2);
Packet packet3(message3); // Runtime time error! Packet does not support Message3 type.

etl::imessage& m1 = message1;
Packet packet4(m1); // Construct from an etl::imessage reference.

etl::imessage& m3 = message3;
Packet packet4(m3); // Asserts etl::unhandled_message_exception! Packet does not support Message3 type.

etl::imessage& m = packet2.get(); // Get a reference to an etl::imessage from the packet.

message_packet.h