Extension for GNU Readline Library Example: require "readline" include Readline line = readline("Prompt> ", true) [Readline] readline(prompt, add_history=nil) Reads one line with line editing. The inputted line is added to the history if add_history is true. completion_proc = proc Specifies a Proc object to determine completion behavior. It should take input-string, and return an array of completion candidates. completion_proc Returns the completion Proc object. completion_case_fold = bool Sets whether or not to ignore case on completion. completion_case_fold Returns true if completion ignores case. completion_append_character = char Specifies a character to be appended on completion. Nothing will be appended if an empty string ("") or nil is specified. completion_append_character Returns a string containing a character to be appended on completion. The default is a space (" "). vi_editing_mode Specifies VI editing mode. emacs_editing_mode Specifies Emacs editing mode. HISTORY The history buffer. It behaves just like an array.