> For the complete documentation index, see [llms.txt](https://trizen.gitbook.io/sidef-lang/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://trizen.gitbook.io/sidef-lang/programming_tasks/m/mad_libs.md).

# Mad Libs

```ruby
var story = ARGF.slurp;
 
var blanks = Hash.new;
while (var m = /<(.*?)>/.gmatch(story)) {
    blanks.append(m[0]);
}
 
blanks.keys.sort.each { |blank|
    var replacement = Sys.scanln("#{blank}: ");
    blanks{blank} = replacement;
}
 
print story.gsub(/<(.*?)>/, {|s1| blanks{s1} });
```