Re: [boost] [variant] match()

Le 09/01/15 10:06, Antony Polukhin a écrit :

2015-01-09 8:10 GMT+03:00 Vicente J. Botet Escriba

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I have started two separated C++ proposals for overload [1] and match [2]

In case some have suggestions for improving them, Vicente

[1] https://github.com/viboes/tags/blob/master/doc/ proposals/overload/DXXXX_Overload.md [2] https://github.com/viboes/tags/blob/master/doc/proposals/match/DXXXX_Match.m...

I like the idea of `overload` more than the `match` idea. `match` looks like a function that does two things: constructs an overloaded function object and applies it as a visitor. While the first thing could be widely usable, the visitation part applies only to the variant. This makes the `overload` method (that is not bound to variant) more usable than `match`.

As I said, match can be applied to any sum type. The github repository contain examples for boost::variant, either(boost::optional) and a selection of possible types for boost::any. It can be applied also to expected, any smart pointer, boost::future or any probably valued type. Hopping this helps to describe the motivation for a function that makes code much safer than using directly functions to check if there is a value and to get it. Best, Vicente