> For the complete documentation index, see [llms.txt](https://kafkawannafly.gitbook.io/generic-collections/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://kafkawannafly.gitbook.io/generic-collections/getting-started/readme.md).

# Quickstart

{% hint style="info" %}
Document page is under construction. Code is cooking.

This notice will be removed once everything is ready to serve.
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### Hello, My Old Friend

Generic was not a thing in Golang until v1.18 (Feb 2022). We're implementing different types of data structures which adopt generic feature. People can enjoy type checking and have better developer experience.

```powershell
go get github.com/KafkaWannaFly/generic-collections
```

<figure><img src="/files/3zGBFFW8eUuAwYMGzdSP" alt=""><figcaption><p>Family Tree</p></figcaption></figure>

Overall, we have `ICollection`, an interface that all structs have implemented. Plus, `HashMap`, a wrapper of built-in map with some convenient methods.

### Working with Struct

This library works well with basic, primitive data-type. If you have any custom struct, which usually yes, you should implement `IHashCoder` and `ILesser` interfaces. They're used by library under the hood. E.g. `Set` would use `IHashCoder` to determine if 2 objects are the same. `List` would use `ILesser` when sorting items.

#### Example

```go
type Book struct {
	Title         string
	Author        string
	CurrentPage   int
	Pages         []string
	PublishedYear int
	Price         float64
}

// A book is define by its title
// If 2 books has same title, they're considered to be equal
func (receiver Book) HashCode() string {
	return receiver.Title
}

// Compare with other book by the title
func (receiver Book) Less(other Book) bool {
	return receiver.Title < other.Title
}
```

#### Interface Definition

{% tabs %}
{% tab title="IHashCoder" %}

```go
package interfaces

type IHashCoder interface {
	// HashCode returns the hash code of the object.
	// Two objects that are equal should have the same hash code.
	HashCode() string
}
```

{% endtab %}

{% tab title="ILesser\[TType any]" %}

```go
package interfaces

type ILesser[TType any] interface {
    // Less checks if the current item is less than the given item.
    Less(TType) bool
}
```

{% endtab %}
{% endtabs %}

#### Can I Use Struct Without Implementing the Above Interfaces?

{% hint style="success" %}
Yes, you can. The system will try to convert your struct into a string to compare.&#x20;
{% endhint %}

#### **What If My Object Can’t Be Converted?**

{% hint style="danger" %}
GGWP  ╮（╯＿╰）╭
{% endhint %}