get_message_tupleT_get_message_tupleGetMessageTupleGetMessageTupleget_message_tuple (Operator)

Name

get_message_tupleT_get_message_tupleGetMessageTupleGetMessageTupleget_message_tuple — Retrieve a tuple associated with the key from the message.

Signature

get_message_tuple( : : MessageHandle, Key : TupleData)

Description

get_message_tupleget_message_tupleGetMessageTupleGetMessageTupleGetMessageTupleget_message_tuple retrieves a tuple associated with the KeyKeyKeyKeykeykey from the message denoted by the MessageHandleMessageHandleMessageHandleMessageHandlemessageHandlemessage_handle. The tuple has to be previously stored to the message using set_message_tupleset_message_tupleSetMessageTupleSetMessageTupleSetMessageTupleset_message_tuple.

The operator returns the data in the parameter TupleDataTupleDataTupleDataTupleDatatupleDatatuple_data. The data including strings is copied by the operation, the message can thus be immediately reused.

If the given KeyKeyKeyKeykeykey is not present in the message or if the data associated with the key is not a tuple, get_message_tupleget_message_tupleGetMessageTupleGetMessageTupleGetMessageTupleget_message_tuple fails. Presence of keys and information about the data associated with the key can be verified using get_message_paramget_message_paramGetMessageParamGetMessageParamGetMessageParamget_message_param.

Execution Information

Multithreading type: reentrant (runs in parallel with non-exclusive operators).
Multithreading scope: global (may be called from any thread).
Processed without parallelization.

Parameters

MessageHandleMessageHandleMessageHandleMessageHandlemessageHandlemessage_handle (input_control) message → (handle)

Message handle.

Number of elements: MessageHandle == 1

Restriction: MessageHandle != 0

KeyKeyKeyKeykeykey (input_control) string → (string / integer)

Key string or integer.

Number of elements: Key == 1

TupleDataTupleDataTupleDataTupleDatatupleDatatuple_data (output_control) tuple(-array) → (string / integer / real / handle)

Tuple value retrieved from the message.

Example (HDevelop)

* ...
get_message_param (Message,'key_exists',['simple_string','foo','my_image'],\
                   KeysPresence)
get_message_param (Message,'key_data_type',['simple_string','my_image'],\
                   KeysType)
get_message_tuple (Message,'simple_string',TupleString)

Result

If the operation succeeds, get_message_tupleget_message_tupleGetMessageTupleGetMessageTupleGetMessageTupleget_message_tuple returns 2 (H_MSG_TRUE). Otherwise an exception is raised. Possible error conditions include invalid parameters (handle or key), the required key not found in the message, or other than tuple data associated with given key.