set_message_tuple — Add a key/tuple pair to the message.
set_message_tuple stores a tuple associated with a key in the
message, which behaves as a dictionary-like data container.
The message is denoted by the
TupleData including strings is copied by the operation, and can
thus be immediately reused.
An empty tuple is considered as a valid value that can be associated with
If any data (tuple or object) was already associated with given key
Key), the old data is destroyed by
and replaced by
Key has to be a string or an integer.
String keys are treated case sensitive.
The tuple data for the given key can be retrieved again from the message
Note that if the tuple contains any handles (which are treated as simple integers) only the handle values are copied by the operation, not the resources behind those handles.
This operator modifies the state of the following input parameter:
During execution of this operator, access to the value of this parameter must be synchronized if it is used across multiple threads.
MessageHandle(input_control, state is modified) message
Number of elements: MessageHandle == 1
MessageHandle != 0
→(string / integer)
Key string or integer.
Number of elements: Key == 1
→(string / integer / real / handle)
Tuple value to be associated with the key.
create_message (Message) set_message_tuple (Message, 'simple_integer', 27) set_message_tuple (Message, 'simple_string', 'Hello world') set_message_tuple (Message, 'mixed_tuple', ['The answer', 42])
If the operation succeeds,
set_message_tuple returns 2 (H_MSG_TRUE).
Otherwise an exception is raised. Possible error conditions include
invalid parameters (handle or key) or resource allocation error.