Display the text for the 99 Bottles of Beer song.

For this, I'm using s:evaluate to construct words which display a string when called. This lets the majority of the code read nicely.

~~~{ 'bottle 'bottles 'of 'beer 'on 'the 'wall 'no 'more 
  'Take 'one 'down, 'pass 'it 'around } 
[ dup ':%s_'%s_s:put_sp_; s:format s:evaluate ] a:for-each 
~~~

Handling of the exact text related to the number of bottles is done with a simple array of functions that get selected based on the number of bottles left. This is done with a very simple filter, where the number of bottles for the purpose of the text is in a set of 2 or more, 1, or none.

~~~{ [ no more bottles      ] 
  [ #1 n:put sp bottle   ] 
  [ dup n:put sp bottles ] 
} 'BOTTLES const 
 
:number-bottles 
  dup #2 n:min BOTTLES swap a:fetch call ; 
~~~

Thanks to the programatically generated words for the verse text, the main code is nicely readable.

~~~:display-verse 
  number-bottles of beer on the wall  nl 
  number-bottles of beer              nl 
  n:dec Take one down, pass it around nl 
  number-bottles of beer on the wall  nl ; 
 
:verses (n-) 
  repeat 0; nl display-verse again ; 
 
#99 verses  
~~~