Exceptions
$! latest error message
$@ location of error
IO
$_ string last read by gets
$/ input record separator
$\ output record separator
$< concatenation stream of files given on input, or $stdin
$> default output for print functions, defaults to $stdout
$FILENAME current input file from $< (i.e. $<.filename)
$stdin standard input stream
$stdout standard output stream
$stderr standard error stream
Processes
$. line number last read by interpreter
$0 the name of the ruby script file
$* the command line arguments
$$ interpreter's process ID
$? exit status of last executed child process
Regular Expressions
$~ the last regexp match on thread, as a MatchData
$& string last matched by regexp (i.e. $~.string)
$` the string before last match (i.e. $~.pre_match)
$' the string after the last match (i.e. $~.post_match)
$+ the contents of the last matched group (i.e. $~[-1])
$n the <n>th group in the last match, e.g. $1 (i.e. $~[n])
$= Deprecated. false (default) indicates case insensive matching by default
Misc
$, default separator for Array.join (nil default == none)
$; default separator for String.split (string or regex, nil default =
whitespace)
$: load path for scripts/binaries when using require
$" all loaded scripts by require
$LOAD_PATH same as $:
$DEBUG status of debug / -d switch
$VERBOSE status of verbose / -v switch
$-0
based on:
http://www.ruby-doc.org/docs/UsersGuide/rg/globalvars.html
http://www.zenspider.com/Languages/Ruby/QuickRef.html
