D7794: rust-nodemap: generic NodeTreeVisitor
gracinet (Georges Racinet)
phabricator at mercurial-scm.org
Mon Jan 27 10:54:59 EST 2020
gracinet added inline comments.
gracinet marked 2 inline comments as done.
INLINE COMMENTS
> martinvonz wrote in nodemap.rs:264-269
> There will only be a valid result if this is a leaf, so it might be better to combine `leaf` and `opt` into one `Option<Option<Revision>>` so the caller cannot mistake a `opt=None` for "missing" when `leaf=false`.
I understand your concern, but `<Option<Option<Revision>>` would defeat the purpose of not having a dead match arm to fill with a "can't happen" comment in the future `insert()`.
Fortunately, @kevincox suggestion of having `NodeTreeVisitor` emit a `struct` provides us with the best of both worlds, since it can have methods.
It should be fully transparent performance-wise, I just hope that is really true.
REPOSITORY
rHG Mercurial
CHANGES SINCE LAST ACTION
https://phab.mercurial-scm.org/D7794/new/
REVISION DETAIL
https://phab.mercurial-scm.org/D7794
To: gracinet, #hg-reviewers, kevincox
Cc: martinvonz, durin42, kevincox, mercurial-devel
More information about the Mercurial-devel
mailing list