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0 pointsCyberDildonics5y ago0 comments

I think that is a giant design mistake since you are pushing the discovery of an error to some place else in the program, potentially very far from where the error occurred.

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luckydude5y ago

Without providing an example of how to do it better, I'm not sure I see your point. Yeah, I see the problem you point out.

Consider

char *p = 0;

some complicated code that should have set p but didn't...

char c = *p; // SEGV

So do you have a way to push that error all the way back to wherever you think it should be pushed?

CyberDildonicsOP5y ago

The person you replied to asked what the behavior was when you access an offset of an array that doesn't exist and you are giving me an example of dereferencing a null pointer.

The array access should error out on the line that it happens.

The dereference could print a line of the last assignment, but this isn't what was being talked about.

luckydude5y ago

I don't see the array access as any different than a null pointer dereference, in both cases you are asking for something that isn't there.

In Tcl, stuff just gets auto expanded on assignment and returns "" (I think) on dereference. We chose to return undef. I'm not sure what the problem is.

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luckydude5y ago

Without providing an example of how to do it better, I'm not sure I see your point. Yeah, I see the problem you point out.

Consider

char *p = 0;

some complicated code that should have set p but didn't...

char c = *p; // SEGV

So do you have a way to push that error all the way back to wherever you think it should be pushed?

CyberDildonicsOP5y ago

The person you replied to asked what the behavior was when you access an offset of an array that doesn't exist and you are giving me an example of dereferencing a null pointer.

The array access should error out on the line that it happens.

The dereference could print a line of the last assignment, but this isn't what was being talked about.

luckydude5y ago

I don't see the array access as any different than a null pointer dereference, in both cases you are asking for something that isn't there.

In Tcl, stuff just gets auto expanded on assignment and returns "" (I think) on dereference. We chose to return undef. I'm not sure what the problem is.

1 more reply

j / k navigate · click thread line to collapse