But if you do want multimethod dispatch, why immediately starting with a corner case?

This may be a corner case for multi-method dispatch. But this kind of argument pattern matching (and by pattern matching I dont mean reg-exp) is quite common in functional languages, especially in recursive functions. Consider this these list functions in Standard ML, they all have an empty list case; 

fun prod [ ] = 1
  | prod (h::t) = h * (prod t);

fun sum [ ] = 0
  | sum (h::t) = h + (sum t);

fun length [ ] = 0
  | length (h::t) = 1 + (length t);

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When pattern matching against arguments in recursive functions like this (and in rescursive multi-method dispatch) it is always good to consider (and explicity code for) your edge cases, otherwise you run the risk of infinite recursion.

-stvn

In reply to Re^2: Hello Perl 6. Running pugs on Windows by stvn
in thread Hello Perl 6. Running pugs on Windows by pernod

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