Add DAP debugging to NeoVim on Mac

Question

Upgrading from vim to neovim (on the mac).

Part of this is to get the DAP debugger working from inside neovim.
I have "Lazy" installed to handle plugins.

I found that the best DAP adapter for g++ (Clang on the Mac) is the llvm lldb-dap which makes sense. I could not find any instructions on how to install it so I came up with the following.

Note this is the file used by "Lazy" to install "nvim-dap".

  return {
      "mfussenegger/nvim-dap",
      config = function(_, _)

          if (vim.loop.os_uname().sysname == "Darwin") then
              local handle = io.popen("brew --prefix")
              local output = handle:read("*a")
              local install = string.gsub(output .. "/opt/llvm/bin/lldb-dap", "\n", "")
              vim.print("lldb: " .. install)
              local exists=io.open(install,"r")
              if exists==nil then
                  vim.print("Could not find lldb-dap. Use `brew install llvm` to install")
              else
                  io.close(exists)

                  local dap = require('dap')

                  dap.adapters.lldb = {
                      type = 'executable',
                      command = install,
                      name = 'lldb'
                  }


                  dap.configurations.cpp = {
                      {
                          name = 'Launch',
                          type = 'lldb',
                          request = 'launch',
                          program = function()
                              return vim.fn.input('Path to executable: ', vim.fn.getcwd() .. '/', 'file')
                          end,
                          cwd = '${workspaceFolder}',
                          stopOnEntry = false,
                          args = {},

                      },
                  }
              end
          end
      end,
  }

Note: I am not familiar with the Lua language so this is from scraps I found around the internet. Any advice on improving the code would be appreciated.

Also any advice on how neovim plugins work would also be helpful.