Problem Statement

Comma quibbling is a task originally set by Eric Lippert in his blog.

Write a function to generate a string output which is the concatenation of input words from a list/sequence where:

Test your function with the following series of inputs showing your output here on this page:

Note: Assume words are non-empty strings of uppercase characters for this task.

Let's start with the solution:

: quibbing(l) -- string
| i s |
   StringBuffer new "{" <<
   l size dup 1- ->s loop: i [ 
      l at(i) <<
      i s < ifTrue: [ ", " << continue ]
      i s == ifTrue: [ " and " << ]
      ]
   "}" << dup freeze ;