Margarida.Core.Linq 1.0.2

Margarida Core Linq

Overview

Library based on Linq that allows you to transform, iterate and query using extensions and also provides some utility methods for .NET Core applications.

Installation

Margarida Core Linq is available as a NuGet package. You can install it using the NuGet Package Console window:

PM> Install-Package Margarida.Core.Linq

Extensions

• For
• Select
• None
• ToCompare
• ChunkBy
• DistinctBy
• InsertAt
• Shuffle
• ForEach
• Most

For

foreach using range

Using kotlin language, when you need to iterate a range there is this native function:

for (int i in 0..9)
    //do something 10x

In C# we need to use the conventional for or use the enumerable extension Range to produce the same effect.

for (var i = 0; i <= 9; i++)
    //do something 10x

foreach (var i in Enumerable.Range(0,9))
    //do something 10x

But using C# 9.0 we can create extensions for implicit indexes. In this package we include this improvement, and you can use that.

Usage

 foreach (var i in 0..9)
    //do something 10x

foreach using multiple variables

When we need iterate two or more sequences, there are a few ways to do it, like using conventional for or combining Linq extensions.

 for (var i = 0; i < sequence1.Count(); i++)
 {
     var itemFromSequenceOne = sequence1[i];
     var itemFromSequenceTwo = sequence2[i];
 }

The problem with using this is that if you have more items in sequence than one another, an out-of-range exception can be a triggered. <br> <br> In this package has been created, an extension to create a tuple between the sequences, and now you can easily iterate the two.

Usage

 foreach (var item in (sequence1,sequence2))
 {
     var itemFromSequence1 = item.item1;
     var itemFromSequence1 = item.item2;
 }

Select

Select with Action

Applies an action to an instance directly and project the instance.

Usage

var person = new Person { Name = "jonh" };
person.Select(x => x.Name = "jonh wick"); // set person name = "Jonh Wick"

Select with Function

Projects a element of a instance into a new form. </br> Invoking a transform function on to an instance and project the instance.

Usage

Person person = new Person { Name = "Jonh Wick" };
var name = person.Select(x => x.Name); // name = "Jonh Wick"

Tip 💡

Sometimes we need to execute a method and keep the instance, but we can't.

var instance = new Instance().SetPropertyValue(1); // SetPropertyValue dont have return.
// Error CS0815  Cannot assign void to an implicitly-typed variable

So we need to define the instance first, then call the method.

var instance = new Instance();
instance.SetPropertyValue(1);

Select with Action resolve this.

var instance = new Instance().Select(x => x.SetPropertyValue(1));

None

Determines whether none element of a sequence exists or satisfies a condition.

var list = new int[] { };
var listAreEmpty = list.None(); //true

list = new int[] { 0, 0, 0 };
var thereNoneGreaterThanZero = list.None(x => x > 0); //true

ToCompare

Compare each items in one sequence with the next.

Usage

var numbers = new[] { 1, 2, 3 };
var allPreviusIsLessThenNext = numbers.ToCompare((x, y) => x < y).All;  // True
var anyPreviusIsLessThenNext = numbers.ToCompare((x, y) => x < y).Any;  // True
var nonePreviusIsLessThenNext = numbers.ToCompare((x, y) => x < y).None;// False

///combining Linq.Extensions in ToCompare for bidirectional enumerables.
var first = new[] { 1, 2, 3 };
var second = new[] { 4, 5, 6 };
var sequenceList = new[] { first, second };
var noneItemInFirstAreInTheSecond = sequenceList.ToCompare((x, y) => x.Intersect(y).Any()).None;

ChunkBy

Splits the elements of a sequence into chunks of size at most size.

Usage

new[] { 1, 2, 3, 4 }.ChunkBy(2); // [ { 1, 2 }, { 3, 4 }]

DistinctBy

Returns distinct elements from a sequence by using a comparer.

Usage

new[] { 1, 1, 1, 2 }.DistinctBy(x => x); // { 1, 2 }

InsertAt

Insert into specific index a value, and move the next ones forward.

Usage

new[] { -1, 0, 1, 3 }.InsertAt(2, 3); // { -1, 0, 1, 2, 3 }

Shuffle

Shuffle a collection randomly.

Usage

new[] { -1, 0, 1, 3 }.Shuffle() // { 0, 1, 3, -1 }

ForEach

A simple way to write foreach statement in single-line.<br /> Executes a action or a body-action for each element in an enumerable.

Usage

new[] { 1, 2, 3 }.ForEach(x => 
    Console.WriteLine(x)
);

Output:
1
2
3

Most

var list = new[] { 1, 3, 2, 4, 0, -1 };
int top;

top = list.Most((x, y) => x < y); // returns the smallest of a list.
Console.WriteLine(top);

top = list.Most((x, y) => x > y); // returns the biggest of a list.
Console.WriteLine(top);

Output:
-1
 4