Fuzion • Idioms • Idiom # 18: Depth-first traversing of a tree

Idiom # 18: Depth-first traversing of a tree

Code

node(T type,
     val T,
     children Sequence (node T)) is

  traverse (f T -> unit) unit =>
    f val
    for child in children do
      child.traverse f

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node(T type,
     val T,
     children Sequence (node T)) is
  traverse (f T -> unit) unit =>
    f val
    for child in children do
      child.traverse f
 
 
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
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What are effects?

Running Example

ex18 is

  node(T type,
       val T,
       children Sequence (node T)) is

    traverse (f T -> unit) unit =>
      f val
      for child in children do
        child.traverse f

  blatt(val String) => node val (list (node String)).empty
  t := node "lion" [blatt "cougar",
                    blatt "elephant",
                    node "hornet" [blatt "bee", blatt "ant"],
                    blatt "beatle2"]

  t.traverse (x -> say x)

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ex18 is
  node(T type,
       val T,
       children Sequence (node T)) is
    traverse (f T -> unit) unit =>
      f val
      for child in children do
        child.traverse f
  blatt(val String) => node val (list (node String)).empty
  t := node "lion" [blatt "cougar",
                    blatt "elephant",
                    node "hornet" [blatt "bee", blatt "ant"],
                    blatt "beatle2"]
  t.traverse (x -> say x)
 
 
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
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What are effects?

last changed: 2025-05-13

next: Idiom # 19: Reverse a list