Yet another segfault (a.k.a. Darkhog is a total noob)

[phibermon]

Oh fair enough I was going off some page I googled in terms of Assigned which showed three definitions, just checked in FPC and yes it's built in.

http://stackoverflow.com/questions/4...ssigned-vs-nil

May as well use assigned. doesn't make a blind bit of difference really. If you're dealing with method pointers to methods that return pointers/objects then using assigned will help you avoid making mistakes I suppose but if you were doing that and used pointers / nil comparisons a lot then you wouldn't make that mistake anyway. Well you'd hope

[Murmandamus]

Well, here's the point. For some implementations, Assigned() may not be just a simple Nil check. For example, let's say that the Foo implementation of FPC does a Nil check AND a check for "0xbaadf00d" (uninitialized data value) to determine if a pointer is valid. If you port your code to Foo, which just checks Nil with a conditional, it may cause an unintended side effect.

Practically, they are identical, but methodologically, they aren't. It goes back to the same reasons why it is bad to do pointer arithmetic, as in C-like languages... pointers need to be treated as opaque types, and depending on them being specific constant values is just generally a bad practice overall (and why Object Pascal is a much superior language than, say C++).