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Comment by ryao | Hacker News Reader

“this” is a reserved keyword in C++, so you do not need to worry about it being a global variable.

That said, I like having a this pointer explicitly passed as it is in C with ADTs. The functions that do not need a this pointer never accidentally have it passed from the developer forgetting to mark the function static or not wanting to rewrite all of the function accesses to use the :: operator.

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It’s not about ‘this’ being a global, it’s if you see ‘i++’ in code it’s not obvious if ‘i’ is a member or not without having to check context.

If you see "i++" in code and you don't have any context about what "i" is, then what difference does it make if "i" is a member variable, global variable, parameter, etc etc...

If all you see in code is a very tiny 3 character expression, you won't be able to make much of a judgement about it to begin with.

Not allowing a variable to implicitly refer to a member variable makes it much easier to find. If it is not declared in the function and there is no implicit dereferencing of a this pointer, the variable is global. If the variable name is commonly used and it is a member variable, it is a nightmare to hunt for the correct declaration in the codebase with cscope.

Good point. I had misunderstood the previous comment as suggesting that this be passed to the member function as an explicit argument, rather than requiring dereferences of this be explicit. The latter makes far more sense and I agree it makes reasoning about things much easier.

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