Re^4: How will you use state declared variables in Perl6?

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]

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Comment on Re^4: How will you use state declared variables in Perl6? Select or Download Code

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Re^5: How will you use state declared variables in Perl6? by TimToady (Parson) on Nov 06, 2006 at 06:18 UTC
You must be running an older pugs. In fact, the current (working) version in the pugs repository (r14657) now reads: `sub fib (UInt $n) { (state $seen = [0,1,1]).[$n] //= fib($n-1) + fib($n-2); }` [download] It would also work as `state @seen = 0,1,1` except there's a bug with initializing state variables using a list that causes it to reinitialize every time instead of just the first time, which, while it lets it run, kinda defeats the memoization...	[reply] [d/l]

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Re^5: How will you use state declared variables in Perl6?
by TimToady (Parson) on Nov 06, 2006 at 06:18 UTC

sub fib (UInt $n) {
    (state $seen = [0,1,1]).[$n] //= fib($n-1) + fib($n-2);
}
[download]

state @seen = 0,1,1

[reply]
[d/l]