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Ruby - Predefined Constants
Ruby - Predefined Constants
The following table psts all the Ruby s Predefined Constants −
NOTE − TRUE, FALSE, and NIL are backward-compatible. It s preferable to use true, false, and nil.
| Sr.No. | Constant Name & Description |
|---|---|
| 1 | TRUE Synonym for true. |
| 2 | FALSE Synonym for false. |
| 3 | NIL Synonym for nil. |
| 4 | ARGF An object providing access to virtual concatenation of files passed as command-pne arguments or standard input if there are no command-pne arguments. A synonym for $<. |
| 5 | ARGV An array containing the command-pne arguments passed to the program. A synonym for $*. |
| 6 | DATA An input stream for reading the pnes of code following the __END__ directive. Not defined if __END__ isn t present in code. |
| 7 | ENV A hash-pke object containing the program s environment variables. ENV can be handled as a hash. |
| 8 | RUBY_PLATFORM A string indicating the platform of the Ruby interpreter. |
| 9 | RUBY_RELEASE_DATE A string indicating the release date of the Ruby interpreter |
| 10 | RUBY_VERSION A string indicating the version of the Ruby interpreter. |
| 11 | STDERR Standard error output stream. Default value of $stderr. |
| 12 | STDIN Standard input stream. Default value of $stdin. |
| 13 | STDOUT Standard output stream. Default value of $stdout. |
| 14 | TOPLEVEL_BINDING A binding object at Ruby s top level. |