2 releases
0.1.2  Mar 13, 2020 

0.1.1 

0.1.0  Mar 11, 2020 
#618 in Algorithms
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Used in 4 crates
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traversal
Traversal implements generic and lazy tree traversal algorithms.
Includes:
 BreadthFirst Traversal (
Bft
)  DepthFirst Traversal in PreOrder (
DftPre
)  DepthFirst Traversal in PostOrder (
DftPost
)  Reverse DepthFirst Traversal in PreOrder (
DftPreRev
)  Reverse DepthFirst Traversal in PostOrder (
DftPostRev
)
 All Paths (
DftPaths
)  Longest Paths (
DftLongestPaths
)  All Cycles (Paths) (
DftCycles
)
Generic
Traversal uses generics (or type parameters) to be flexible to use, and easy to implement and fit into existing architecture.
Laziness
Laziness or lazy evaluation refers to evaluation being delayed until needed.
Traversal delays processing Node
s and fetching child Node
s
until Iterator::next
is called.
When next
is called, then traversal only processes the
Node
s required for this iteration.
From Rust's docs:
Iterators (and iterator adapters) are lazy. This means that just creating an iterator doesn't do a whole lot. Nothing really happens until you call
next
.
Usage
Add this to your Cargo.toml
:
[dependencies]
traversal = "0.1"
Releases
Release notes are available in the repo at CHANGELOG.md.
Algorithms
A
/ \
B C
/ \ / \
D E F G
Given the above tree, then the following are the orders, that each individual iterator / traversal algorithm produces.
Algorithm  Order 

Bft (BreadthFirst Traversal) 
A, B, C, D, E, F, G 
DftPre (DepthFirst Traversal in PreOrder) 
A, B, D, E, C, F, G 
DftPost (DepthFirst Traversal in PostOrder) 
D, E, B, F, G, C, A 
DftPreRev (Reverse DepthFirst Traversal in PreOrder) 
G, F, C, E, D, B, A 
DftPostRev (Reverse DepthFirst Traversal in PostOrder) 
A, C, G, F, B, E, D 
See each individual algorithm for code examples.
All Paths and Longest Paths
DftPaths
and DftLongestPaths
are utilities for
iterating all paths and the longest paths in a tree.
Given the same tree as the previous examples, then
DftPaths
and DftLongestPaths
produce the
following paths.
 A, B
 A, B, D
 A, B, E
 A, C
 A, C, F
 A, C, G
 A, B, D
 A, B, E
 A, C, F
 A, C, G
See each individual algorithm for code examples.
Cycles
A <+
/ \ 
B D >+
  
C E >+
 A > D (implies D is connected with A)
 A > D > E
See each individual algorithm for code examples.