~/s/_/crystal > crystal run test.cr
Unhandled exception: Argument 'flag' ("something") must start with a dash (-) (ArgumentError)
  from /Users/andremedeiros/.asdf/installs/crystal/0.34.0/src/option_parser.cr:200:7 in 'check_starts_with_dash'
  from /Users/andremedeiros/.asdf/installs/crystal/0.34.0/src/option_parser.cr:196:11 in 'check_starts_with_dash'
  from /Users/andremedeiros/.asdf/installs/crystal/0.34.0/src/option_parser.cr:117:5 in 'on'
  from test.cr:6:3 in '__crystal_main'
  from /Users/andremedeiros/.asdf/installs/crystal/0.34.0/src/crystal/main.cr:105:5 in 'main_user_code'
  from /Users/andremedeiros/.asdf/installs/crystal/0.34.0/src/crystal/main.cr:91:7 in 'main'
  from /Users/andremedeiros/.asdf/installs/crystal/0.34.0/src/crystal/main.cr:114:3 in 'main'