Agreement on Parameter Specializers and Qualifiers

ToC

Allegro CL

ANSI Common Lisp

Two methods are said to agree with each other on parameter specializers and qualifiers if the following conditions hold:

1. Both methods have the same number of required parameters. Suppose the parameter specializers of the two methods are P_1,1 ... P_1,n and P_2,1 ... P_2,n.
2. For each 1 <= i <= n, P_1,i agrees with P_2,i. The parameter specializer P_1,i agrees with P_2,i if P_1,i and P_2,i are the same class or if P_1,i=(eql object₁), P_2,i=(eql object₂), and (eql object₁ object₂). Otherwise P_1,i and P_2,i do not agree.
3. The two lists of qualifiers are the same under equal.