ClassArgument

ClassArgument -- an option name for method which allows one argument to the method function to be interpreted as a class in its own right.

f = method(ClassArgument => {false,true}) -- provides a list of boolean values, the n-th of which specifies whether the n-th argument presented to the the method function, rather than its class, will participate in the search for a method function.

The code above creates a function named 'f' which takes up to three arguments, looking up the appropriate method according to its arguments, with inheritance. To install a method for two arguments, (x,Y), where x is of class X, use code like this:

          f(X,Y) := (x,Y) -> ...

where '...' represents the body of the function you wish to install. The syntax for one or three arguments is analogous.

We give two examples for contrast.

     i1 = f = method ();

     i2 = f(ZZ,QQ) := print;

     i3 = f(3,3/2)
     
       3
     3,-
       2

The method function used above was effectively found as the value of lookup(f,class 3, class 3/2) .

     i4 = g = method (ClassArgument => {false,true});

     i5 = g(ZZ,QQ) := print;

     i6 = g(3,QQ)
     
     3,QQ

The method function used above was effectively found as the value of lookup(f,class 3, QQ) . Notice that QQ , the second argument, participated directly, rather than its class.

This option is incompatible with the Associativeoption, and hasn't yet been implemented in conjunction with the Options option.