beginner implementation of Catamorphism for non binary trees versus the Composite Design Pattern

For the moment, the dream still goes on, at each haskell concept I learn I am more enticed. Yet I havent completely fulfilled working on this precious @luqui\'s answer to my previous question about ca

Catamorphism and tree-traversing in Haskell

I am impatient, looking forward to understanding catamorphism related to this SO question :) I have only practiced the beginning of Real World Haskell tutorial. So, Maybe I\'m gonna ask for way too m

Scala type inference question

I was just pottering about with Tony Morris\' excellent exercise on catamorphisms, when I was pondering what was happening in the following situation...

购火车票网站有哪些？