Frontmatec.Linq 1.0.4

Frontmatec.Linq

ForEach

Performs the specified action on each element of the sequence.

IsSingle

Determines whether the 'source' contains exactly one element.

| Method                  | Mean             | Error          | StdDev          | Gen0   | Allocated |
|------------------------ |-----------------:|---------------:|----------------:|-------:|----------:|
| EnumerableIsSingleCheck |        36.047 ns |      0.7604 ns |       1.9492 ns | 0.0172 |      72 B |
| EnumerableCountCheck    | 1,980,981.136 ns | 39,473.5803 ns | 104,678.3429 ns |      - |       6 B |
| ListIsSingleCheck       |         5.989 ns |      0.1412 ns |       0.2280 ns |      - |         - |
| ListCountCheck          |         7.008 ns |      0.1774 ns |       0.2306 ns |      - |         - |

MergeSorted

Merges two sorted sequences into a single sorted sequence.

var first = new List<int> { 1, 4, 7 };
var second = new List<int> { 2, 5, 8 };
var merged = first.MergeSorted(second, (a, b) => a <= b ? -1 : 1);

| first:  1  4  7
| second:  2  5  8
|------------------
| merged: 12 45 78

Flatten Method

The FlattenTree method is an extension method for IEnumerable<T> that flattens a tree of elements into a flat sequence. It supports both depth-first and breadth-first traversal orders.

Usage

Given the following tree:

        1
       / \
      2   3
     / \
    4   5

Depth-First Traversal

Depth-first traversal processes each node and its children before moving on to the next sibling node. This is the default traversal order.

var result = collection.FlattenTree(x => x.Children); // [1, 2, 4, 5, 3]
var result = collection.FlattenTree(x => x.Children, TraversalOrder.DepthFirst); // [1, 2, 4, 5, 3]

Breadth-First Traversal

Breadth-first traversal processes all nodes at the current level before moving on to the next level.

var result = collection.FlattenTree(x => x.Children, TraversalOrder.BreadthFirst); // [1, 2, 3, 4, 5]

Benchmarking

If you have an idea for a faster or better implementation, then replace the 'FlattenContender' method with your own implementation and run the benchmarks ('dotnet run -c release' in terminal for the Frontmatec.Linq.Tests project).

Current benchmark as of 10/02/2025:

| Method                                            | NodeCount | Mean      | Error     | StdDev    | Gen0   | Allocated |
|-------------------------------------------------- |---------- |----------:|----------:|----------:|-------:|----------:|
| FlattenTree_SingleCollection_BreadthFirst         | 10        |  1.256 ns | 0.0474 ns | 0.0466 ns |      - |         - |
| FlattenTree_MultipleCollections_BreadthFirst      | 10        |  1.184 ns | 0.0304 ns | 0.0285 ns |      - |         - |
| FlattenTree_SingleCollection_DepthFirst           | 10        |  1.246 ns | 0.0326 ns | 0.0304 ns |      - |         - |
| FlattenTree_MultipleCollections_DepthFirst        | 10        |  1.288 ns | 0.0475 ns | 0.0584 ns |      - |         - |
| FlattenContender_SingleCollection_DepthFirst      | 10        |  7.972 ns | 0.1769 ns | 0.1655 ns | 0.0056 |      88 B |
| FlattenContender_MultipleCollections_DepthFirst   | 10        |  8.807 ns | 0.0958 ns | 0.0849 ns | 0.0056 |      88 B |
| FlattenContender_SingleCollection_BreadthFirst    | 10        | 11.952 ns | 0.1037 ns | 0.0970 ns | 0.0107 |     168 B |
| FlattenContender_MultipleCollections_BreadthFirst | 10        | 11.630 ns | 0.1337 ns | 0.1251 ns | 0.0107 |     168 B |