Problem:
`:restart` does not preserve window layout, etc.
Solution:
- Change `:restart` to save/restore a session automatically.
- Introduce "bang" variant `:restart!` to restart *without* session
save/restore.
- Introduce `v:startreason`.
- `ZR` maps to `:restart!`.
(cherry picked from commit 845b66dd4a)
Problem:
It's clumsy for scripts to handle a "restart", without custom mappings or
global vars.
Solution:
Introduce `v:startreason`
(cherry picked from commit ae426ee465)
Problem:
`v:starttime`, `:uptime` use a monotonic high-resolution timer. This
only works as long as the timer keeps running (if the computer is
suspended the timer is paused). This is somewhat unintuitive, and
doesn't match the behavior of the `uptime` shell command.
Solution:
Implement `os_realtime` to get the real time since the
epoch in nanoseconds.
Problem:
- Not obvious which _meta/ are generated and which should be edited
manually.
- The require guard (`error('Cannot require a meta file')`) is not
consistently present in all meta files.
Solution:
- Update headers.
- Add require() guard to all meta files.
- Rename generated meta files with `.gen.lua`.
(cherry picked from commit 65b40e69ac)
