compiler flag for "preview all"

[Dennis]

On Monday, 29 June 2020 at 23:31:16 UTC, Bruce Carneal wrote:
> So, any objections to preview=all meaning "enable all known 
> preview items"?

I wouldn't object, but I wouldn't find 'all *known* preview 
items' useful since the status of the switches varies a lot.

I personally try to enable dip25, dip1000, fieldwise, markdown, 
fixAliasThis, intpromote, and dtorfields for my projects. I 
especially like markdown in DDoc, and dip25+dip1000 enabling 
@safe use of stack memory.

I don't use the following switches:

nosharedaccess: tried it, but it gave some compile errors I 
couldn't be bothered to fix
rvaluerefparam: cool feature, but DIP is in 'GitHub gist' state 
(not even draft review), so it's not certain this will actually 
become part of the language
dip1008: I don't need @nogc Exceptions it, from what I heard it's 
in a buggy state
dip1021: useless switch that gives 100% false positives (see DIP 
review). I tried to enable it, it gave a compile error in Phobos 
std.uni.CowArray, and ended in a dmd segfault