Based on the example above, I think we need               to be more explicit about how the  method is               handled.                                  There are really two different sets of statics             that need to be handled by the class initialization:            A) common statics (shared across all             instantiations)           B) specialized statics           In addition to the statics, there is also             common (and maybe specialized?) code that is run as part of             .                          
    There is a reasonable model to collapse these back into one concept;     treat "common statics" as specialized statics on the all-erased     parameterization, with a  clause that restricts them to     that parameterization.  Not clear whether we actually want to     represent it that way or not, but its a useful mental model that     doesn't require the creation of a third thing.  (Since Class[Foo]     and ParamType[Foo,erased*] describe the same class, this is also     fully binary compatible with existing classes.)  
    
    Which means we can do a similar thing with , if we     want.  I'll wave my hands because we've not yet talked much about     conditional members, but it basically looks like this:
    
    
    () { /* common static init code */
                   /* specializable init code */ }
    
    () { /* specializable init code */ }
    
    Or not.  
    
    
                                      Where will the initialization code for both kinds of statics           be?  The existing  method?                     
    
    We have two choices:
     - have a new  block that gets run once per     specialization, and keep 
     - merge the two as above, exploiting planned support for     conditional members
    
    Either way, as you say, we have to ensure that the common init runs     exactly once.  
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Based on the example above, I think we need to be more explicit about how the method is handled.
There are really two different sets of statics that need to be handled by the class initialization:
A) common statics (shared across all instantiations)
B) specialized statics
In addition to the statics, there is also common (and maybe specialized?) code that is run as part of .

There is a reasonable model to collapse these back into one concept; treat "common statics" as specialized statics on the all-erased parameterization, with a clause that restricts them to that parameterization. Not clear whether we actually want to represent it that way or not, but its a useful mental model that doesn't require the creation of a third thing. (Since Class\[Foo\] and ParamType\[Foo,erased\*\] describe the same class, this is also fully binary compatible with existing classes.)

Which means we can do a similar thing with , if we want. I'll wave my hands because we've not yet talked much about conditional members, but it basically looks like this:


() { /\* common static init code \*/
/\* specializable init code \*/ }

() { /\* specializable init code \*/ }

Or not.

Where will the initialization code for both kinds of statics be? The existing method?

We have two choices:
\- have a new block that gets run once per specialization, and keep
\- merge the two as above, exploiting planned support for conditional members

Either way, as you say, we have to ensure that the common init runs exactly once.
When using \*static, are we only discussing {get,put}? Or is this also proposing invokestatic changes to allow specialized static methods?

Methods too.

All of the technical details aside, is this something we really want to expose to the users? They're going to have a hard time understanding why Foo (or Foo & Foo share the erased version.

I think this is mostly a matter of coming up with the right syntax, which makes it clear that statics can be per-class or per-specialization. There are a whole pile of related specialization-related syntax issues, I'll try to get them all in one place.