[darcs-users] [patch35] Reduce scope of Darcs.Patch.Choices.pull... (and 1 more)

[Petr Rockai]

Hi Eric,

Eric Kow <kowey at darcs.net> writes:
> Sun Oct 11 17:07:44 BST 2009  Eric Kow <kowey at darcs.net>
>   * Reduce scope of Darcs.Patch.Choices.pull_first.
>   Pull_firsts makes use of it and seems to discard some of the intermediary
>   results.  I want to ensure that changing these intermediary results does
>   not have unintended consequences.
this one is clear, if it compiles it works.

> Sun Oct 11 19:09:47 BST 2009  Eric Kow <kowey at darcs.net>
>   * Remove completely superfluous negTag mechanism.
>   This change is really due to Kamil Dworakowski, who observed that pull_firsts
>   returns all the InFirst patches along with the InMiddle patches they depend on
>   without any tags.
But I have my doubts about this. I mean, although pull_firsts does not care
about the tag value in itself, it leaks the tags which are examined in other
parts of the code for equality. I'll have to carefully go through all the code
dealing with those tags to understand whether this is a good idea at all.

I also think that the comment for Tag, although well-intended, is pretty
confusing, since it emphasises implementation details instead of the actual
important bits. What it's trying to say is that Tag is a patch label that is
*unique within a sequence*, and the whole "pointer" stuff is just a handy
mechanism to guarantee that uniqueness (also, calling that a "pointer" is
rather ... unorthodox).

Yours,
   Petr.