• Robbert Krebbers's avatar
    Support introduction patterns /=, {H}, {$H} in iDestruct. · 686f5740
    Robbert Krebbers authored
    This fixes issue #57.
    I considered supporting these introduction patterns also in a nested fashion --
    for example allowing `iDestruct foo as [H1 [{H1} H1 /= H2|H2]` -- but that
    turned out to be quite difficult.
    Where should we allow `/=`, `{H}` and `{$H}` exactly. Clearly something like
    `>/=` makes no sense, unless we adopt to some kind of 'stack like' semantics
    for introduction patterns as in ssreflect. Alternatively, we could only allow
    these patterns in the branches of the destructing introduction pattern
    `[... | ... | ...]` but that brings other complications, e.g.:
    - What to do with `(H1 & /= & H3)`?
    - How to distinguish the introduction patterns `[H _]` and `[_ H]` for
      destructing a spatial conjunction? We cannot simply match on the shape of the
      introduction pattern anymore, because one could also write `[_ H /=]`.