[Vm-dev] [OpenSmalltalk/opensmalltalk-vm] Provide control over VM messages (#275)

[David T. Lewis]

On Sun, Aug 19, 2018 at 10:31:15AM -0700, Fabio Niephaus wrote:
>  
> @akgrant43 also thinks a command line flag would be the way to go here (see https://github.com/OpenSmalltalk/opensmalltalk-vm/pull/279#issuecomment-414133977).
> 
> Here's one last argument against it that I can think of: the option parser fails on unknown options and that means that CI scripts can only use, e.g., a `-suppress*` option iff supported by the vm, otherwise it will fail. The only way to make that work is to check the version of the vm before opening an image, which in turn adds complexity to CI scripts.
> 

For the unix VM, command line arguments are (or should be) supported by
environment variables. See function vm_parseEnvironment() for environment
variables that match with various corresponding command line arguments.

If you follow this pattern, then you woould define a new command line parameter
as previously suggested, and also a new environment variable to do the same
thing. With that approach, you can use the environment variable that does
what you want, rather than adding special-case handling for ${CI}.

Dav