Um. Er...? 

pugs>sub fib (Int $n) { return 1 if $n < 2; state @seen[$n] //= fib($n
+-1) + fib($n-2); }
Internal error while running expression:
***
    unexpected "["
    expecting word character, "::", "=", ":=", "::=", ";" or "}"
    at <interactive> line 1, column 52

[download]

Update: This works though 

pugs>  sub fib (Int $n) { state @seen; return 1 if $n < 2; @seen[$n] /
+/= fib($n-1) + fib($n-2); };
undef
pugs> say fib 4;
5
undef
pugs> say fib 8;
34
undef
pugs> say fib 800;
1121023813016570197539221312040081070329432498024398917379911096096424
+176870242714672419719090010009284331740160122026805305229708722215290
+03044406006693244742562963426
undef

[download]
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^4: How will you use state declared variables in Perl6? by BrowserUk
in thread How will you use state declared variables in Perl6? by Limbic~Region

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