tree a4e5874edca54d2b3c26cb6e0da36a6c4341cbb3
parent 476e75ded71ad6f573daabe2ca7a1be9fe3ce3cb
author Nicholas Nethercote <nnethercote@mozilla.com> 1568693984 +1000
committer Nicholas Nethercote <nnethercote@mozilla.com> 1568698349 +1000

Remove `NodeIndex`.

The size of the indices doesn't matter much here, and having a
`newtype_index!` index type without also using `IndexVec` requires lots
of conversions. So this commit removes `NodeIndex` in favour of uniform
use of `usize` as the index type. As well as making the code slightly
more concise, it also slightly speeds things up.