Re: Re (tilly) 1: Recursive generation of a sorted list from a hash

in reply to Re (tilly) 1: Recursive generation of a sorted list from a hash
in thread Recursive generation of a sorted list from a hash

Thanks.

It doesn't handle circular references..in fact, I think that is why it fails at the moment. I'm going to add some logic in there to see if a node has already been processed, and post the changes.

Comment on Re: Re (tilly) 1: Recursive generation of a sorted list from a hash

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Re: Re: Re (tilly) 1: Recursive generation of a sorted list from a hash by hawson (Monk) on Mar 23, 2001 at 22:38 UTC
A fairly simple change to my script fixed the problem. In each call to `&Recurse` I additionally pass a `@stack` list. This list contains all of the 'parent' nodes in the call tree. So when the function runs, it checks to see if the node is present in `@stack`, then I know there is circular reference. So, the inital invocation of `&Recurse` becomes: `&Recurse($_,())`, and subsequent calls (the truly recursive ones) turn into: `&Recurse($node,@stack,$node)`. This works, although tilly has a much more compact solution. :-)	[reply] [d/l] [select]

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Re: Re: Re (tilly) 1: Recursive generation of a sorted list from a hash
by hawson (Monk) on Mar 23, 2001 at 22:38 UTC

&Recurse

@stack

So, the inital invocation of &Recurse becomes: &Recurse($_,()), and subsequent calls (the truly recursive ones) turn into: &Recurse($node,@stack,$node).

This works, although tilly has a much more compact solution. :-)

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