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:

comma-quibble lst:
	"}" )
	if lst:
		pop-from lst
		if lst:
			" and "
			pop-from lst
			for item in lst:
				item ", "
	concat( "{"

!. comma-quibble []
!. comma-quibble [ "ABC" ]
!. comma-quibble [ "ABC" "DEF" ]
!. comma-quibble [ "ABC" "DEF" "G" "H" ]