set_message_param
— Set message parameter or invoke commands on the message.
set_message_param( : : MessageHandle, GenParamName, Key, GenParamValue : )
set_message_param
sets message
parameters or invokes action commands on the message.
For each call of set_message_param
, only a single parameter can be
set. However, there are two types of parameters/commands:
Parameters/commands applicable to the entire message. In this case
no keys must be specified, i.e., the parameter Key
must be an empty
tuple.
Parameters/commands applicable to the individual keys. In this case a
non-empty list of keys must be specified in parameter Key
. The
keys are processed in the same order as specified in the Key
parameter.
Key-independent parameter names:
Removes all the keys currently stored in the message and releases
all the (control or iconic) data associated with those keys.
The operation results in an empty message.
Note that contents of GenParamValue
is ignored for this
parameter, while Key
must be an empty tuple.
Key-specific parameter names:
Removes the keys specified in the Key
parameter and releases
all the (tuple or object) data associated with those keys.
If an error occures while processing one or more keys (in particular
if the key is invalid), the operator attempts to continue removing
as many keys as possible before reporting the failure.
Note that the contents of GenParamValue
is ignored for this
parameter.
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 →
(handle)
Message handle.
Number of elements: MessageHandle == 1
Restriction: MessageHandle != 0
GenParamName
(input_control) string →
(string)
Names of the message parameters or action commands.
Number of elements: GenParamName == 1
Default value: 'remove_key'
List of values: 'remove_all_keys' , 'remove_key'
Key
(input_control) string(-array) →
(string / integer)
Message keys the parameter/command should be applied to.
GenParamValue
(input_control) tuple(-array) →
(string / integer / real)
Values of the message parameters or action commands.
* Remove some keys set_message_param (Message, 'remove_key', ['my_image', 'simple_string'], [])
If all the operator parameters, and their values, as well as specified
keys are valid, set_message_param
returns 2 (H_MSG_TRUE).
Otherwise an exception is raised.
dequeue_message
,
create_message
enqueue_message
,
clear_message
create_message
,
clear_message
,
set_message_tuple
,
get_message_tuple
,
set_message_obj
,
get_message_obj
,
get_message_param
,
enqueue_message
,
dequeue_message
Foundation