Allowing PortGroups to bump port revision

[René J.V. Bertin]

On Saturday January 13 2018 16:19:10 Clemens Lang wrote:

Hi,

This went into my junk folder so I'm only seeing it now.


>This could be made much faster if Tcl had a way to 'clone' an
>interpreter that already had port1.0 loaded before running the rest of
>the Portfile. If somebody wants to implement that, that would probably
>improve portindex speeds significantly.

I suppose it should, esp. if Tcl doesn't compile expressions into some internal binary representation.

On top of that it would probably help if you could make an existing parsing context read-only so you can cut down on stack recursion. I don't know if that makes much sense; I did this once for an interpreter I wrote. Allows it to evaluate 2 or 3 levels of constant expressions without having to create new stack frames for things as simple as initialising a variable with a constant or from another variable **). It did require a tedious bit of code writing but it gave a nice extra boost (though much less than implementing a byte/JIT compiler).

**) Portfiles contain lots of that kind of expression, but I hope Tcl's parser is a little more involved than the simple contraption I wrote when so much younger.