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0 pointsLvl999Noob1d ago0 comments

What if Go went all the way? Referencing a zero pointer (nil) gives you the zero value of the pointed to type. If you try to access a zero map, it tries to deference the zero pointer to the underlying buffer. The zero pointer gives you the zero slice with zero length. The presence check fails without crashing and you get some pretension of reasonable behaviour.

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clausecker1h ago

Really bad idea.

Silently returning some (the wrong) value is always worse than catching the error right then and their and panicking. A panic is a noticeable symptom of something just having go wrong that is easy to chase after and debug. A silently returned wrong value just causes data corruption down the line, at great pain. It is very annoying to debug, in particular if people start to some times rely on this behaviour as an intentional part of their data flow.

ptman1d ago

So what happens when you write through the nil pointer?

Lvl999NoobOP1d ago

Well, what happens when you write through an invalid pointer? The runtime can swallow the write or crash the program or allocate new storage and replace the pointer. Depends on the wanted semantics.

chuckadams1d ago

Nil of course (nothing happens). Not saying it’s a good idea, it would just be consistent.

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