On 8/15/05, Kripa Sundar <[EMAIL PROTECTED]> wrote: > Dear Uri, > > Thanks to you and the others for your prompt responses. > > > another bad point about eval is that it can access and modify lexicals > > and globals anywhere in the code. so that can lead to action at a > > distance and very hard to find bugs. > > I don't quite follow. > > Globals are anyway accessible. How does eval() make things worse? > > How can lexicals that are outside the scope of the eval statement be visible? [...]
I'm not sure if this is what is referred to, but it applies. If this is dynamic code where the string to be evaled is passed in from elsewhere, then one problem is that you might wind up picking up lexicals in the scope of the eval, and being unable to pick up lexicals in the scope where you tried to create the eval. Closures would get this right. Ruby solves this problem by giving you a number of variations on eval, one of which evals things in the context of your caller. Still not perfectly general, but much more likely to be right in this instance. Cheers, Ben _______________________________________________ Boston-pm mailing list Boston-pm@mail.pm.org http://mail.pm.org/mailman/listinfo/boston-pm
