<[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] | Hi all, | | As I understand it, the idea behind duck typing is that you just take | an object and if it has the methods you want to use you use it | assuming it to be the right type of object. I'm interested in | extending this idea a bit, but I feel the sort of thing I have in mind | has already been thought of. So for example, in the program I'm | writing a 'state variable' specifier can be either an integer or a | string (the string name is mapped to an integer by another function | getvarindex(name)).
Why a function rather than a dict 'varindex'? The valid strings are then varindex.keys(). You might want a build_varindex() func though. |In this case, I can't do duck typing by seeing if | the object has a method or not, because both of the types are built in | types. builtin types have methods same as user types. It is not clear from your description why there should be any restriction on state-variable specifier other than hashable since any set of hashable objects can be easily mapped to range(len(<specifier-set>) with a dict. Whether you merely document the rules or write code to enforce them should partly depends on who suffers when they are broken. tjr -- http://mail.python.org/mailman/listinfo/python-list
