启动 ruby 时如何解决此错误？答案

【问题标题】：How do I resolve this error when starting ruby?启动 ruby 时如何解决此错误？
【发布时间】：2020-10-05 01:07:10
【问题描述】：

运行 ruby bin/start 时出现此错误。有人可以帮我理解该怎么做吗？

Traceback (most recent call last):
        4: from bin/start:4:in `<main>'
        3: from bin/start:4:in `require_relative'
        2: from /Users/ivana/Desktop/online_projects/NYC Park CLI/lib/environment.rb:3:in `<top (required)>'
        1: from /Users/ivana/.rvm/rubies/ruby-2.6.1/lib/ruby/site_ruby/2.6.0/rubygems/core_ext/kernel_require.rb:92:in `require'
/Users/ivana/.rvm/rubies/ruby-2.6.1/lib/ruby/site_ruby/2.6.0/rubygems/core_ext/kernel_require.rb:92:in `require': cannot load such file -- pry (LoadError)
        22: from bin/start:4:in `<main>'
        21: from bin/start:4:in `require_relative'
        20: from /Users/ivana/Desktop/online_projects/NYC Park CLI/lib/environment.rb:3:in `<top (required)>'
        19: from /Users/ivana/.rvm/rubies/ruby-2.6.1/lib/ruby/site_ruby/2.6.0/rubygems/core_ext/kernel_require.rb:156:in `require'
        18: from /Users/ivana/.rvm/rubies/ruby-2.6.1/lib/ruby/site_ruby/2.6.0/rubygems/core_ext/kernel_require.rb:168:in `rescue in require'
        17: from /Users/ivana/.rvm/rubies/ruby-2.6.1/lib/ruby/site_ruby/2.6.0/rubygems/core_ext/kernel_require.rb:168:in `require'
        16: from /Users/ivana/.rvm/gems/ruby-2.6.1/gems/pry-0.13.1/lib/pry.rb:78:in `<top (required)>'
        15: from /Users/ivana/.rvm/rubies/ruby-2.6.1/lib/ruby/site_ruby/2.6.0/rubygems/core_ext/kernel_require.rb:72:in `require'
        14: from /Users/ivana/.rvm/rubies/ruby-2.6.1/lib/ruby/site_ruby/2.6.0/rubygems/core_ext/kernel_require.rb:72:in `require'
        13: from /Users/ivana/.rvm/gems/ruby-2.6.1/gems/pry-0.13.1/lib/pry/cli.rb:134:in `<top (required)>'
        12: from /Users/ivana/.rvm/gems/ruby-2.6.1/gems/pry-0.13.1/lib/pry/cli.rb:40:in `add_plugin_options'
        11: from /Users/ivana/.rvm/gems/ruby-2.6.1/gems/pry-0.13.1/lib/pry/cli.rb:40:in `each'
        10: from /Users/ivana/.rvm/gems/ruby-2.6.1/gems/pry-0.13.1/lib/pry/plugins.rb:55:in `load_cli_options'
         9: from /Users/ivana/.rvm/rubies/ruby-2.6.1/lib/ruby/site_ruby/2.6.0/rubygems/core_ext/kernel_require.rb:92:in `require'
         8: from /Users/ivana/.rvm/rubies/ruby-2.6.1/lib/ruby/site_ruby/2.6.0/rubygems/core_ext/kernel_require.rb:92:in `require'
         7: from /Users/ivana/.rvm/gems/ruby-2.6.1/gems/pry-byebug-3.7.0/lib/pry-byebug/cli.rb:5:in `<top (required)>'
         6: from /Users/ivana/.rvm/rubies/ruby-2.6.1/lib/ruby/site_ruby/2.6.0/rubygems/core_ext/kernel_require.rb:72:in `require'
         5: from /Users/ivana/.rvm/rubies/ruby-2.6.1/lib/ruby/site_ruby/2.6.0/rubygems/core_ext/kernel_require.rb:72:in `require'
         4: from /Users/ivana/.rvm/gems/ruby-2.6.1/gems/pry-byebug-3.7.0/lib/pry-byebug/commands.rb:12:in `<top (required)>'
         3: from /Users/ivana/.rvm/rubies/ruby-2.6.1/lib/ruby/site_ruby/2.6.0/rubygems/core_ext/kernel_require.rb:72:in `require'
         2: from /Users/ivana/.rvm/rubies/ruby-2.6.1/lib/ruby/site_ruby/2.6.0/rubygems/core_ext/kernel_require.rb:72:in `require'
         1: from /Users/ivana/.rvm/gems/ruby-2.6.1/gems/pry-byebug-3.7.0/lib/pry-byebug/commands/exit_all.rb:3:in `<top (required)>'
/Users/ivana/.rvm/gems/ruby-2.6.1/gems/pry-byebug-3.7.0/lib/pry-byebug/commands/exit_all.rb:7:in `<module:PryByebug>': uninitialized constant Pry::Command::ExitAll (NameError)

【问题讨论】：

您的环境中似乎没有安装 pry 或 pry-byebug（或两者） gem。尝试运行gem info pry 以确保已安装
它安装我得到 pry (0.13.1, 0.12.2, 0.11.3, 0.10.3) pry-byebug (3.7.0) 当运行 gem list
Ruby 知道如何找到您的 GEM 吗？ IE。你的环境变量GEM_HOME 设置正确吗？
如果你使用bundler，你还需要将gem "pry"添加到你的Gemfile并运行bundle。 /仅仅安装 gem 是不够的，bundler 还必须知道它。
@holgerJust 是的，我的 Gemfile 中有 gem pry

标签： ruby command-line-interface

【解决方案1】：

事实证明，问题可能源于您使用稍旧的pry-byebug 3.7.0 以及最新的pry 0.13.1。

不幸的是，在 pry 0.13.0 中有一些更改需要更新 pry-byebug 才能使用此版本。根据Changelog of pry-byebug 3.9.0，他们在此版本中添加了对 pry 0.13 的初始支持（并删除了对任何旧 pry 版本的支持）。

因此，要解决此问题，您应该将 pry-byebug 版本升级到 3.9.0 或将 pry 版本降级到低于 0.13 的版本。根据您在 Gemfile 中指定依赖项的准确程度，只需运行以下命令即可升级您的 pry-byebug 版本：

bundle upgrade

【讨论】：