Traversing tree and stopping halfway in Haskell

Posted by Michael War on Stack Overflow See other posts from Stack Overflow or by Michael War
Published on 2010-06-03T16:18:17Z Indexed on 2010/06/03 16:24 UTC
Read the original article Hit count: 203

Filed under:

haskell

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functional-programming

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tree

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traversal

I want to traverse a tree and return changes to the tree whilst doing so. The result should be a Maybe monad, with Just tree if it succeeds otherwise None.

The question is, what is the cleanest way to stop with the traversing half-way and return None if necessary?

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