Return the as bound value of the variable, constant, or
expression. The as bound value of an IConstant is the
contant's value. The as bound value of an IVariable is the
bound value in the given IBindingSet -or- null if
the variable is not bound in the IBindingSet.
bindingSet - The binding set.
The as bound value of the constant, variable, or expression.
java.lang.IllegalArgumentException - if this is an IVariable and the bindingSet is
java.lang.String toString(int indent)
A string representation of a recursive structure with pretty-print indent.