RE: [eigen] "plain": a new keyword for auto with implicit evaluation

[<Daniel.Vollmer@xxxxxx>]

Hello,

since we're all inserting cents:

> If Eigen were to make a break with C++03 compatibility it might as well be all the way

> to the latest standard in my opinion.

Not everyone is so lucky that they either already have a code-base in C++17, or can just trivially require it (with all that that entails for the host system, compiler, and other dependencies used).

I personally don't see a problem with requiring C++11 in a new major release, but anything newer than that should IMO be weighed *very* carefully against the features / simplifications / etc. it allows.

Best regards

Daniel Vollmer

--------------------------
Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR)
German Aerospace Center
Institute of Aerodynamics and Flow Technology | Lilienthalplatz 7 | 38108 Braunschweig | Germany

Daniel Vollmer | AS C²A²S²E
www.DLR.de

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Von: Wood, Tobias [tobias.wood@xxxxxxxxx]
Gesendet: Dienstag, 19. Februar 2019 12:23
An: eigen@xxxxxxxxxxxxxxxxxxx
Betreff: Re: [eigen] "plain": a new keyword for auto with implicit evaluation

> Just my two cents, might be a bit off-topic here, but in my opinion it would be a real back-step if the "hypothetical" Eigen 4 was stuck on C++11. I would very strongly argue to at least make the step to full C++14 and potentially C++17

 

I wholeheartedly agree on this point. C++17 features have been a big help in my own code - I have a hunch that `if constexpr` has the potential to simplify parts of Eigen (but this is a vague hunch based on my own code and a poor understanding of Eigen’s template code). If Eigen were to make a break with C++03 compatibility it might as well be all the way to the latest standard in my opinion.

 

Toby