can I set the constraints for a variable once and generate a few times in specman?

Question

I have a variable that I want to generate a few times in the same function, each time with the same set of constraints. Can I set the constraints once and the just gen it many times? That is, instead of this:

var a:uint;
gen a keeping {it in [100..120];};
// some code that uses a
.
.
.
gen a keeping {it in [100..120];};
// some code that uses a
.
.
.
gen a keeping {it in [100..120];};
// some code that uses a
// etc...

I'd like to do this:

var a:uint;
keep a in [100..120];
.
.
.
gen a;
// some code that uses a
.
.
.
gen a;
// some code that uses a
.
.
.
gen a;
// some code that uses a
// etc...

That way if I want to change as constraints I only have to do it once.

Answer 1

You can do this by making the variable an instance member of the enclosing object.

a : uint;
keep a in [100..120];
my_method()@qualified_clk_rise_e is {

    gen a;
    ...
    gen a;
    ...
    gen a; 
};

This implementation isn't thread-safe if multiple my_method()'s are running on the same object at the same time.You can make it [specman] thread-safe by assigning the generated 'a' to a 'my_a' within the scope of the method:

var my_a : uint;
gen a;
my_a = a;

Or you can just write a method to generate 'a':

gen_a(): uint is {
    gen result keeping { it in [100..120] };
};

my_method()@qualified_clock_rise_e is {
    var a : uint;
    ...
    a = gen_a();
    ...
    a = gen_a();
    ...
    a = gen_a();
    ...
};