set_difference! Compute and update the difference of two sets
package require nstcl-misc ?1.0?
package require nstcl ?1.0?
::nstcl::set_difference! set_name set
Computes the difference of the set stored in the variable named set_name in the calling environment and the set set, sets the variable named set_name in the calling environment to that difference, and also returns that difference.