Question

i have singleton class , when calling one of the singleton methods more then once in the same time , and this method has local variables . does each method call of the singleton gets its own private stack , do i need to worry about sharing/mixing local variable data between calls ?

Answer 1

Using local variables in a class method (not important whether it is a singleton) is no different from using local variables in a regular function. The local variables will not get mixed up.