eq forces scalar context and is meant to compare strings

So in the first code you are checking if the sizes (after stringification) are equal.

  DB<107> @a = 1..3
 => (1, 2, 3)
 
  DB<108> @a eq "3"
 => 1
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in the second you have scalar from reverse on RHS

  DB<123> (reverse @a)
 => (3, 2, 1)
 
  DB<124> scalar (reverse @a)
 => 321
 
  DB<125> "321" eq (reverse @a)
 => 1
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please stop doing weird things!

you can try the (less weird) smart match operator ~~ to compare arrays.

  DB<129> @a=(3,1,3)
 => (3, 1, 3)
 
  DB<130> @a ~~ [reverse @a]
 => 1
 
  DB<131> @a ~~ [3,1,3]
 => 1
 
  DB<132> @a=1..3
 => (1, 2, 3)
 
  DB<133> @a ~~ [reverse @a]
 => ""
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a poor man's solution with eq is to explicitly stringify on both sides.

  DB<143> @a=(3,1,3)
 => (3, 1, 3)
 
  DB<144> @ar=reverse @a
 => (3, 1, 3)
 
  DB<145> "@a"
 => "3 1 3"
 
  DB<146> "@a" eq "@ar"
 => 1
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But this depends on the nature of your array elements, don't be too surprised about:

  DB<151> "@a"
 => "3 1 3"
 
  DB<152> @b=(3,"1 3")
 => (3, "1 3")
 
  DB<153> "@a" eq "@b"
 => 1
[download]