[Pharohbot]

As stated before, there are ways to avoid them and ways that Nim will soon handle them, but do you know how many other languages deref a NULL pointer? Unlike C, this does not result in undefined behavior in means that it will execute something unsafe in Nim

[jessaustin]

Sorry for my ignorance, but the languages other than C that I've used are javascript, python, various lisps, bash, sql, prolog, etc.: no pointers! I'm interested to learn how pointers might be made safe, in Nim or anywhere else?

[Pharohbot]

It really depends on how you define "safe". Nim will allow you to deref null pointers (unless you annotate it with `not nil`, then it can never be nil, this results in compile errors if it is) but if they are, it will be like Java and throw an exception if --nilChecks:On. The only language I know that makes pointers safe is Rust, with it's borrow checker and such, but that's a tradeoff I don't really want and the options Nim provides are better for my case.

[pjmlp]

Ada, SPARK, ParaSail

[pcwalton]

It is undefined behavior in Nim due to compiling to C. https://news.ycombinator.com/item?id=9050999

[Pharohbot]

As stated before in this thread, there _will_ be nil Checks in the future which will result in NilErrors or you can just annotate it with `not nil` right now and it will never be nil. You can also use -fsanitize flags with the clang backend to trap the null dereferences.

[jibalt]

"Unlike C, this does not result in undefined behavior "

Of course it does. If you turn off expensive runtime checks, you'll get SIGSEGVs. That doesn't happen in Rust, because it is semantically impossible to dereference NULL.

[Pharohbot]

Since when were we comparing Nim and Rust? yes Rust is more safe than Nim, but that comes with tradeoffs. You are obviously not reading the whole thread about me bringing up (multiple times) the fact that you can avoid these and will be even easier to avoid in the future.