Final by default?

[Walter Bright]

On 3/12/2014 5:40 PM, Vladimir Panteleev wrote:
> Doesn't this sort of seal the language's fate in the long run, though?
> Eventually, new programming languages will appear which will learn from D's
> mistakes, and no new projects will be written in D.
>
> Wasn't it here that I heard that a language which doesn't evolve is a dead
> language?
>
>  From looking at the atmosphere in this newsgroup, at least to me it appears
> obvious that there are, in fact, D users who would be glad to have their D code
> broken if it means that it will end up being written in a better programming
> language. (I'm one of them, for the record; I regularly break my own code anyway
> when refactoring my library.) Although I'm not advocating forking off a D3 here
> and now, the list of things we wish we could fix is only going to grow.

There are costs and benefits:

Benefits:

1. attracting new people with better features

Costs:

2. losing existing users by breaking their code, losing new people because of a 
reputation for instability

There aren't clearcut answers. It's a judgement call. The final-by-default has 
very large breakage costs, and its improvement is minor and achievable by other 
means.