Set Object Varialbe to Nothing - why?

[Harry Flashman]

Excel VBA Variables. Using Variables in Excel VBA Macro Code
The above webpage offers the following advice about object variables:

Set rMyCell = Range("A1")

"So when we have finished using the Object Variable "rMyCell" it is a good idea to Set it back to it's default value of Nothing. eg: [...] This will mean Excel will not be reserving unnecessary memory."

Set rMyCell = Nothing

Could some please explain the issue here. Is the writer simply referring to memory used while the macro is running or is he also referring to Excel reserving memory even after the macro has finished running?

I occasionally see people set Object variable to nothing at the end of the code - but since the macro is finished what is the point of this?

Cheers

 

[diddi]

harry, when a variable is Set, it is allocated a place in memory. by setting to Nothing, this invokes a VBA command to release the memory for the OS again. it not only has no value, but is no longer part of the programs scope. it is good practice to remove objects from memory as they can be quite large and soon clog up working space.
hope that make sense.

 

[Harry Flashman]

harry, when a variable is Set, it is allocated a place in memory. by setting to Nothing, this invokes a VBA command to release the memory for the OS again. it not only has no value, but is no longer part of the programs scope. it is good practice to remove objects from memory as they can be quite large and soon clog up working space.
hope that make sense.

Okay I am going to get into the habit of setting object variables to nothing when I have finished with them. Back to the second part of my quesition - if the object variable is not set to Nothing does it still take up memory once the routine has finished running? Or is that memory released automatically once the routine is finished?

 

[diddi]

the variables are all wiped from memory when the subroutine finishes execution providing they are not set as public or global with a module. that is excels memory management at work.

 

[Harry Flashman]

the variables are all wiped from memory when the subroutine finishes execution providing they are not set as public or global with a module. that is excels memory management at work.

Thanks for clearing that up. Cheers.