Scalars can be declared globally or locally inside a procedure. There is only one name-space for global declarations so all identifiers must be unique within all the files provided to a single execution of rwloadsim. Most declarations can be made private which implies they are only available in the rwl input file in which they are declared.
All simple variables can be initialized at declaration time, and all variables declared outside functions and procedures are global by default. When worker threads are started, variables are initialized to their values from the main thread, except for variables with the threads sum attribute, which are initialized as zero in worker threads, and summed to the value in the main thread after worker threads finish.
Variables of type type integer, double, string can be declared with the threads global attribute implying only one copy of the variable exists. Internal data structures of such variables are protected by a mutex, making it safe to read and write the variable in multiple threads.
Variables declared with the private keyword are only available in the rwl source file where they are declared. Variables declared inside procedures and functions are local to that procedure or function.
Variables in the first .rwl file named on the command line that also are found as $useroption or $userswitch directives can be initialized at the command line, in which case the command line value will overwrite any value assigned during declaration.
Some example variable declarations:
integer abracadbra := 27, b; $useroption:abracadabra
# declare two integers, the first will be initialized and its value
# can be overwritten by the user using a --abracadabra option.
double threads sum total:=0;
# declare a double, which is initialized and
# which will be summed when workers finish
string(30) filename := "output.txt";
# declare a string and assign it the value "output.txt"
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