Re: [boost] Boost.URL: Something Wicked This Way Comes!

Ahmed Charles wrote:

On Friday, October 15th, 2021 at 5:14 AM, Phil Endecott via Boost wrote:

...

Exactly, it's like returning a string_view from a function - which you should never do, at least not without an obvious indication...

My primary objection to this line of thinking is that the standard begin/end functions have the same dangerous implications as this function does. The input can be a string and the output is something that becomes invalid when that string is destroyed.

I'd be happy with the parsing function returning a view if its name reflected that. My complaint is that the short name parse_url() doesn't give the user that "obvious indication". There are a couple of differences with begin()/end(). Firstly, "everyone knows" that begin() and end() return iterators so the names do give the required clue. Secondly, these are methods, not free functions; you can argue that it's OK to return iterator/pointer/view types from getter methods if the lifetime of the pointee is the same as the object. (Yes I'm conveniently overlooking the begin()/end() free functions.) I'd also suggest that the existence of foot-guns already in the language is not an excuse for adding more! These are not absolute, yes/no decisions; there are trade-offs to be made. The only benefit of naming this view-returning function parse_url() is less typing. I don't think that's worthwhile. Regards, Phil.