Same fringe: Difference between revisions
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m (→{{header|Perl 6}}: useless newline) |
(→{{header|Perl 6}}: the gather {*} thing does not work anymore for some reason) |
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{{Works with|Rakudo|#67 ("Bicycle")}} |
{{Works with|Rakudo|#67 ("Bicycle")}} |
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Unlike in Perl 5, where <tt>=></tt> is just a synonym for comma, in Perl 6 it creates a true Pair object. So here we use Pair objects for our "cons" cells, just as if we were doing this in Lisp. We use the <tt>gather/take</tt> construct to harvest the leaves lazily as the elements are visited with a standard recursive algorithm, using multiple dispatch to differentiate nodes from leaves. The <tt>eqv</tt> value equivalence is applied to the two lists in parallel. |
Unlike in Perl 5, where <tt>=></tt> is just a synonym for comma, in Perl 6 it creates a true Pair object. So here we use Pair objects for our "cons" cells, just as if we were doing this in Lisp. We use the <tt>gather/take</tt> construct to harvest the leaves lazily as the elements are visited with a standard recursive algorithm, using multiple dispatch to differentiate nodes from leaves. The <tt>eqv</tt> value equivalence is applied to the two lists in parallel. |
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<lang perl6> |
<lang perl6>sub samefringe ($a, $b) { fringe($a) eqv fringe($b) } |
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sub fringe ($tree) { |
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multi |
multi sub fringey (Pair $node) { fringey $_ for $node.kv; } |
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multi sub fringey ( Any $leaf) { take $leaf; } |
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gather fringey $tree; |
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} |
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sub samefringe ($a, $b) { fringe($a) eqv fringe($b) }</lang> |
sub samefringe ($a, $b) { fringe($a) eqv fringe($b) }</lang> |
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Testing: |
Testing: |
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