
extsubsop - substituting operands of a domain element

Calling sequence:
extsubsop(domelem [ , equal ... ])

Parameter:
domelem   --  domain element
equal     --  equation with a positive integer on the left side

Summary:

A domain element consists of the domain , to which it belongs, and a listof
values that represent its contents.

extsubsop replaces the operands of the list of the domain element domelem
that correspond to the indicies of the left side of the equation with the relevant
right side of the equation.  If the left side of the equation has the value 0
then the right side of the equation must be a domain.  The function then
replaces the domain to which the domain element belongs with the given
one. extsubsop is a kernel function.

>>  d:=domain(): e:=new(d,1,2,3,4): extsubsop(e,1=5): extop(e,1);

     1

>>  d:=domain(): e:=new(d,1,2,3,4): e:=extsubsop(e,1=5): extop(e,1);

      5

>>  d:=domain(): e:=new(d,1,2,3,4): e:=extsubsop(e,6=8): e;

      new(domain( ), 1, 2, 3, 4, NIL, 8)

See also:  extnops , extop , new, subsop

