Re: NSOutlineView compilation error

[Alexander Malmberg]

> The ## is needed to paste the name of the method being checked for. Simply
> replacing it as you have done *will not work* as now it is looking for a 
> method
> named "selector_name".  The "errors" you mention are preprocessor warnings and
> are harmless.

This is wrong. ## is used to do token concatenation, ie. forming one
token from two tokens. This is not what you want to do here, and gcc is
telling you that it isn't doing it. A simple replacement is correct.

Also, @"data source does not respond to ##selector_name" likely does not
do what it's intended to do, since it's just a normal string constant.
The intention is probably to stringify the selector name, like:

@"data source does not respond to"  @ #selector_name

The cpp manual has all the details.

- Alexander Malmberg