* doc/globals.rdoc: Add documentation file for magic globals

  [ruby-core:29048] [Bug #3022]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@37913 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 61 insertions, 0 deletions

diff --git a/doc/globals.rdoc b/doc/globals.rdoc
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+# -*- mode: rdoc; coding: utf-8; fill-column: 74; -*-
+
+== Pre-defined variables
+
+$!::   The exception information message set by 'raise'.
+$@::   Array of backtrace of the last exception thrown.
+$&::   The string matched by the last successful match.
+$`::   The string to the left  of the last successful match.
+$'::   The string to the right of the last successful match.
+$+::   The highest group matched by the last successful match.
+$1::   The Nth group of the last successful match. May be > 1.
+$~::   The information about the last match in the current scope.
+$=::   The flag for case insensitive, nil by default.
+$/::   The input record separator, newline by default.
+$\::   The output record separator for the print and IO#write. Default is nil.
+$,::   The output field separator for the print and Array#join.
+$;::   The default separator for String#split.
+$.::   The current input line number of the last file that was read.
+$<::   The virtual concatenation file of the files given on command line (or from $stdin if no files were given).
+$>::   The default output for print, printf. $stdout by default.
+$_::   The last input line of string by gets or readline.
+$0::   Contains the name of the script being executed. May be assignable.
+$*::   Command line arguments given for the script sans args.
+$$::   The process number of the Ruby running this script.
+$?::   The status of the last executed child process.
+$:::   Load path for scripts and binary modules by load or require.
+$"::   The array contains the module names loaded by require.
+$DEBUG::     The status of the -d switch.
+$FILENAME::  Current input file from $<. Same as $<.filename.
+$LOAD_PATH:: The alias to the $:.
+$stderr::    The current standard error output.
+$stdin::     The current standard input.
+$stdout::    The current standard output.
+$VERBOSE::   The verbose flag, which is set by the -v switch.
+$-0::  The alias to $/.
+$-a::  True if option -a is set. Read-only variable.
+$-d::  The alias to $DEBUG.
+$-F::  The alias to $;.
+$-i::  In in-place-edit mode, this variable holds the extension, otherwise nil.
+$-I::  The alias to $:.
+$-l::  True if option -l is set. Read-only variable.
+$-p::  True if option -p is set. Read-only variable.
+$-v::  The alias to $VERBOSE.
+$-w::  True if option -w is set.
+
+== Pre-defined global constants
+
+TRUE::              The typical true value.
+FALSE::             The false itself.
+NIL::               The nil itself.
+STDIN::             The standard input. The default value for $stdin.
+STDOUT::            The standard output. The default value for $stdout.
+STDERR::            The standard error output. The default value for $stderr.
+ENV::               The hash contains current environment variables.
+ARGF::              The alias to the $<.
+ARGV::              The alias to the $*.
+DATA::              The file object of the script, pointing just after __END__.
+RUBY_VERSION::      The ruby version string (VERSION was deprecated).
+RUBY_RELEASE_DATE:: The release date string.
+RUBY_PLATFORM::     The platform identifier.
+