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Diffstat (limited to 'doc/optparse/tutorial.rdoc')
| -rw-r--r-- | doc/optparse/tutorial.rdoc | 40 |
1 files changed, 38 insertions, 2 deletions
diff --git a/doc/optparse/tutorial.rdoc b/doc/optparse/tutorial.rdoc index 3474f1e576..ad8486d894 100644 --- a/doc/optparse/tutorial.rdoc +++ b/doc/optparse/tutorial.rdoc @@ -1,6 +1,6 @@ == Tutorial -=== Why OptionParser? +=== Why \OptionParser? When a Ruby program executes, it captures its command-line arguments and options into variable ARGV. @@ -34,6 +34,7 @@ The class also has: === Contents +- {To Begin With}[#label-To+Begin+With] - {Defining Options}[#label-Defining+Options] - {Option Names}[#label-Option+Names] - {Short Option Names}[#label-Short+Option+Names] @@ -50,6 +51,42 @@ The class also has: - {Default Values for Options}[#label-Default+Values+for+Options] - {Argument Converters}[#label-Argument+Converters] +=== To Begin With + +To use \OptionParser: + +1. Require the \OptionParser code. +2. Create an \OptionParser object. +3. Define one or more options. +4. Parse the command line. + +File +basic.rb+ defines three options, <tt>-x</tt>, +<tt>-y</tt>, and <tt>-z</tt>, each with a descriptive string, +and each with a block. + + :include: ruby/basic.rb + +From these defined options, the parser automatically builds help text: + + $ ruby basic.rb --help + Usage: basic [options] + -x Whether to X + -y Whether to Y + -z Whether to Z + +When an option is found during parsing, +the block defined for the option is called with the argument value. + +Executions: + + $ ruby basic.rb -x -z + ["x", true] + ["z", true] + $ ruby basic.rb -z -y -x + ["z", true] + ["y", true] + ["x", true] + === Defining Options A common way to define an option in \OptionParser @@ -361,7 +398,6 @@ Executions: $ ruby default_values.rb --yyy FOO {:yyy=>"FOO", :zzz=>"BBB"} - === Argument Converters An option can specify that its argument is to be converted |