midigrid/MidiGrid_PlayFromBar.lua

--[[
  MIDI Grid: play from the start of the bar the cursor is in, and keep going.

  Deliberately works whether or not grid mode is on -- it is a listening aid,
  not an editing action, and it is just as useful while navigating with OSARA
  normally. Stop with Space as usual.
]]
local dir = ({ reaper.get_action_context() })[2]:match("@?(.*[\\/])")
local G = dofile(dir .. "midigrid_lib.lua")

local bar = G.playFromBar(false)
G.say("Playing from bar " .. bar)