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Writing a 'Mad Libs' program using Ruby?
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JRUBY(1) LOCAL JRUBY(1) NAME
jruby -- Interpreted object-oriented scripting language SYNOPSIS
jruby [--copyright] [--version] [-Sacdlnpswvy] [-0[octal]] [-C directory] [-F pattern] [-I directory] [-K c] [-T[level]] [-e command] [-i[extension]] [-r library] [-x[directory]] [--] [program_file] [argument ...] DESCRIPTION
Jruby is a 100% pure-Java implementation of Ruby, an interpreted scripting language for quick and easy object-oriented programming. It has many features to process text files and to do system management tasks (as in Perl). It is simple, straight-forward, and extensible. OPTIONS
Ruby interpreter accepts following command-line options (switches). They are quite similar to those of perl(1). --copyright Prints the copyright notice. --version Prints the version of Ruby interpreter. -0[octal] (The digit ``zero''.) Specifies the input record separator ($/) as an octal number. If no digit is given, the null character is taken as the separator. Other switches may follow the digits. -00 turns Ruby into paragraph mode. -0777 makes Ruby read whole file at once as a single string since there is no legal character with that value. -C directory Causes Ruby to switch to the directory. -F pattern Specifies input field separator ($;). -I directory Used to tell Ruby where to load the library scripts. Directory path will be added to the load-path variable ($:). -K kcode Specifies KANJI (Japanese) encoding. -S Makes Ruby use the PATH environment variable to search for script, unless if its name begins with a slash. This is used to emulate #! on machines that don't support it, in the following manner: #! /usr/local/bin/ruby # This line makes the next one a comment in Ruby exec /usr/local/bin/ruby -S $0 $* -T[level] Turns on taint checks at the specified level (default 1). -a Turns on auto-split mode when used with -n or -p. In auto-split mode, Ruby executes $F = $_.split at beginning of each loop. -c Causes Ruby to check the syntax of the script and exit without executing. If there are no syntax errors, Ruby will print ``Syntax OK'' to the standard output. -d --debug Turns on debug mode. $DEBUG will be set to true. -e command Specifies script from command-line while telling Ruby not to search the rest of arguments for a script file name. -h --help Prints a summary of the options. -i extension Specifies in-place-edit mode. The extension, if specified, is added to old file name to make a backup copy. For example: % echo matz > /tmp/junk % cat /tmp/junk matz % ruby -p -i.bak -e '$_.upcase!' /tmp/junk % cat /tmp/junk MATZ % cat /tmp/junk.bak matz -l (The lowercase letter ``ell''.) Enables automatic line-ending processing, which means to firstly set $ to the value of $/, and secondly chops every line read using chop!. -n Causes Ruby to assume the following loop around your script, which makes it iterate over file name arguments somewhat like sed -n or awk. while gets ... end -p Acts mostly same as -n switch, but print the value of variable $_ at the each end of the loop. For example: % echo matz | ruby -p -e '$_.tr! "a-z", "A-Z"' MATZ -r library Causes Ruby to load the library using require. It is useful when using -n or -p. -s Enables some switch parsing for switches after script name but before any file name arguments (or before a --). Any switches found there are removed from ARGV and set the corresponding variable in the script. For example: #! /usr/local/bin/ruby -s # prints "true" if invoked with `-xyz' switch. print "true " if $xyz On some systems $0 does not always contain the full pathname, so you need the -S switch to tell Ruby to search for the script if necessary. To handle embedded spaces or such. A better construct than $* would be ${1+"$@"}, but it does not work if the script is being interpreted by csh(1). -v --verbose Enables verbose mode. Ruby will print its version at the beginning, and set the variable $VERBOSE to true. Some methods print extra messages if this variable is true. If this switch is given, and no other switches are present, Ruby quits after printing its version. -w Enables verbose mode without printing version message at the beginning. It sets the $VERBOSE variable to true. -x[directory] Tells Ruby that the script is embedded in a message. Leading garbage will be discarded until the first that starts with ``#!'' and contains the string, ``ruby''. Any meaningful switches on that line will applied. The end of script must be spec- ified with either EOF, ^D (control-D), ^Z (control-Z), or reserved word __END__. If the directory name is specified, Ruby will switch to that directory before executing script. -y --yydebug Turns on compiler debug mode. Ruby will print a bunch of internal state messages during compiling scripts. You don't have to specify this switch, unless you are going to debug the Ruby interpreter. UNIX
Apr 2, 2007 UNIX
