# New Ticket Created by awwa...@thelackthereof.org
# Please include the string: [perl #127749]
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# <URL: https://rt.perl.org/Ticket/Display.html?id=127749 >
Here is an example that works as expected:
> for ^2 { my $n = 5; say [+] (^$n X ^$n) }
50
50
If we use constants to construct the Seq, it is not re-created on the
second loop iteration:
> for ^2 { say [+] (^5 X ^5) }
50
This Seq has already been iterated, and its values consumed
(you might solve this by adding .cache on usages of the Seq, or
by assigning the Seq into an array)
in block <unit> at <unknown file> line 1
In my particular case after building the Seq I was applying map and grep to
it which would change on each iteration -- it yells at me for the
constant-Seq re-use even though I am doing different things with it each
time.
> for ^2 -> $n { say [+] (^5 X ^5).map(* + $n) }
50
This Seq has already been iterated, and its values consumed
(you might solve this by adding .cache on usages of the Seq, or
by assigning the Seq into an array)
in block <unit> at <unknown file> line 1
I don't feel that the suggested .cache is appropriate, but maybe I'm wrong?
Seems like if I wanted this Seq to be shared I should have to define it
before the block.
Note that if I manually unrolled this loop I wouldn't get the error (since
the Seq would be written out twice, so not considered the same Seq).
