>well splice also says

> The following equivalences hold

> ...
> shift(@a)     splice(@a,0,1)

It would appear shift is doing something like this:

  DB<232> x $x=4; while( ($y)= ( $u = splice( @t,0,1 ))){ last unless 
+$x--; print ":$_: " }

 :: :: :: ::  empty array
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which would make the equivalence:

          shift(@a)   ===   ( $t = splice( @a,0,1 ) )
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