In Perl, a range within an array slice behaves as though the individual elements in the range had been specified with comma separators:

11:44 >perl -MData::Dump -we "my @c = 'a'..'z'; dd map { qq[<$_>] } @c
+[6..9, 23, 25];"
("<g>", "<h>", "<i>", "<j>", "<x>", "<z>")

11:45 >

[download]

This is what I would expect. But in Raku, it seems that a range inside an array slice produces an additional layer of grouping:

11:45 >raku -v
This is Rakudo version 2020.05.1 built on MoarVM version 2020.05
implementing Raku 6.d.

11:45 >raku -e "my @c = 'a'..'z'; @c[6..9, 23, 25].map( { qq[<$_>] } )
+.raku.put;"
("<g h i j>", "<x>", "<z>").Seq

11:46 >

[download]

AFAICT, the Raku documentation on subscripts doesn’t explain this. So, I have two questions:

  1. What is the cause of this (to me) strange behaviour? (Is it a feature or a bug?)
  2. How can I use ranges in Raku array slices to achieve the same result I get in Perl (i.e., no additional grouping)?

Thanks,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to [Raku] Ranges in array slices by Athanasius

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