ruby-on-rails - 运行 "rails new"时出现语法错误

Question

当我尝试通过运行创建一个新项目时:

rails new app 

我收到以下错误消息:

/usr/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:121:in `require': /usr/lib/ruby/vendor_ruby/did_you_mean/spell_checkers/method_name_checker.rb:9: syntax error, unexpected '.' (SyntaxError)
      @has_args    = !exception.args&.empty?
                                      ^
    from /usr/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:121:in `require'
    from /usr/lib/ruby/vendor_ruby/did_you_mean.rb:6:in `<top (required)>'
    from /usr/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:121:in `require'
    from /usr/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:121:in `require'
    from /var/lib/gems/2.2.0/gems/thor-0.20.3/lib/thor/error.rb:4:in `<class:Thor>'
    from /var/lib/gems/2.2.0/gems/thor-0.20.3/lib/thor/error.rb:1:in `<top (required)>'
    from /usr/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:69:in `require'
    from /usr/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:69:in `require'
    from /var/lib/gems/2.2.0/gems/thor-0.20.3/lib/thor/base.rb:4:in `<top (required)>'
    from /usr/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:69:in `require'
    from /usr/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:69:in `require'
    from /var/lib/gems/2.2.0/gems/thor-0.20.3/lib/thor.rb:2:in `<top (required)>'
    from /usr/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:121:in `require'
    from /usr/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:121:in `require'
    from /var/lib/gems/2.2.0/gems/railties-5.1.4/lib/rails/command.rb:7:in `<top (required)>'
    from /usr/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:69:in `require'
    from /usr/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:69:in `require'
    from /var/lib/gems/2.2.0/gems/railties-5.1.4/lib/rails/cli.rb:10:in `<top (required)>'
    from /usr/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:69:in `require'
    from /usr/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:69:in `require'
    from /var/lib/gems/2.2.0/gems/railties-5.1.4/exe/rails:9:in `<top (required)>'
    from /usr/local/bin/rails:23:in `load'
    from /usr/local/bin/rails:23:in `<main>'

我不确定发生了什么。这是什么？

Answer 1

安全导航运算符 &. 在 Ruby < 2.3 中无效。你正在使用 Ruby 2.2。这就是语法错误的原因。