------------------------------------------------------------------------
-- subexpr -> (simpleexp | unop subexpr) { binop subexpr }
-- where 'binop' is any binary operator with a priority higher than 'limit'
-- * for priority lookups with self.priority[], 1=left and 2=right
-- * recursively called
-- * used in expr()
------------------------------------------------------------------------

function luaY:subexpr(ls, v, limit)
  self:enterlevel(ls)
  local uop = self:getunopr(ls.t.token)
  if uop ~= "OPR_NOUNOPR" then
    luaX:next(ls)
    self:subexpr(ls, v, self.UNARY_PRIORITY)
    luaK:prefix(ls.fs, uop, v)
  else
    self:simpleexp(ls, v)
  end
  -- expand while operators have priorities higher than 'limit'
  local op = self:getbinopr(ls.t.token)
  while op ~= "OPR_NOBINOPR" and self.priority[luaK.BinOpr[op] + 1][1] > limit do
    local v2 = {}  -- expdesc
    luaX:next(ls)
    luaK:infix(ls.fs, op, v)
    -- read sub-expression with higher priority
    local nextop = self:subexpr(ls, v2, self.priority[luaK.BinOpr[op] + 1][2])
    luaK:posfix(ls.fs, op, v, v2)
    op = nextop
  end
  self:leavelevel(ls)
  return op  -- return first untreated operator
end
