Category
Flow Control
Function
Retrieves an object from the cache. State is not maintained between
executions of any macros containing GetLocal.
Syntax
object, link = GetLocal(object,
reset);
Inputs
| Name
| Type
| Default
| Description
|
| object
| object
| none
| object to be output if nothing
has been set
|
| reset
| flag
| 0
| 0: the object cached by SetLocal
(if there is one) is passed to output
1: object (not the cached object) is passed to
output.
|
Outputs
| Name
| Type
| Description
|
| object
| object
| retrieved object
|
| link
| string
| link to corresponding SetLocal
module
|
Functional Details
GetLocal works with SetLocal to place objects in and retrieve them
from the cache. GetLocal differs from GetGlobal in that GetLocal and
SetLocal are used when the state maintained by the Get/Set pair should be
reset when a macro containing these modules is reexecuted. In contrast,
GetGlobal and SetGlobal will maintain state when the macro is reexecuted.
Note that for a single execution of a macro (for example, throughout
the execution of an entire loop), state is of course maintained by both
GetLocal and GetGlobal.
object
| specifies the object to be output by GetLocal if nothing has
been placed
in the cache (e.g., as on the first execution of a visual program)
or if reset = 1.
|
reset
| causes the module to output object.
If this parameter is set to 0 (zero), GetLocal retrieves the last object
placed in the cache by SetLocal (if there is one).
Otherwise, the module passes object to the output.
|
The link output is to be connected to the
link input of the corresponding SetLocal
module.
GetLocal should always be used with
SetLocal, not with SetGlobal. SetLocal must be executed on the same
machine as GetLocal (i.e., it cannot be distributed to a different
machine).
It is not necessary to use the First tool to provide input to the
reset parameter of GetLocal inside a macro, since
this is done automatically whenever the macro is reexecuted.
A detailed description of the behavior and use of the GetLocal,
GetGlobal, SetLocal, and SetGlobal modules can be found in
4.6 , "Preserving Explicit State" in IBM
Visualization Data Explorer User's Guide.
Example Visual Programs
Accumulate.net
Bounce.net
SimpleGetSetLoop.net
See Also
Done,
First,
SetLocal,
GetGlobal,
SetGlobal,
Reset
Chapter 4. "Data Explorer Execution
Model" in IBM Visualization Data Explorer User's Guide.