The following works in current Rakudo: 

multi fib ($ where 0|1) {1}
multi fib ($i) { fib($i-1) + fib($i-2) }

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According to the relevant design docs I ought to be able to omit the `$ where ` bit but that bit of sugaring has not yet been implemented in Rakudo.

»ö« . o O ( "the celebrity tell-all of the Perl-6 cult?" )

In reply to Re^5: rough approximation to pattern matching using local (Multi Subs) by raiph
in thread rough approximation to pattern matching using local by gregory-nisbet

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