While it might be annoying to use local variables, I usually find it's superior when debugging. It allows you to easily inspect the value and modify it before going forwards.
It also usually helps to make the code more self-documenting
It also usually helps to make the code more self-documenting
Re: self-documenting, certainly sometimes (I mean, you shouldn't play code golf...), but in this case the code in question was:
2218 if (!valid_localpart(maddr->user) ||
2219 !valid_domainpart(maddr->domain)) {
....
2234 return (0);
2235 }
2236
2237 return (1);