niljson/README.md

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# niljson - A simple Go package for unmarshalling null-able JSON types

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niljson provides a simple and efficient way to handle nullable JSON fields during the unmarshalling process. 
In JSON, it's common to encounter fields that can be `null`, but handling these fields in Go can be cumbersome, 
especially when dealing with primitive types like `int`, `float64`, `bool`. These types can all be either `0` (as value)
or `null`. In Go you can always work with pointers but these, of course, can lead to unhandled nil pointer dereferences.

**niljaon** addresses this challenge by offering a set of types that can seamlessly handle `null` values during 
unmarshalling, allowing your Go applications to work with JSON data more naturally and with fewer boilerplate 
checks for `nil` values.

### Key Features

- **Nullable Types**: Provides a range of nullable types (`NilString`, `NilInt`, `NilFloat`, `NilBool`, etc.) that 
  are easy to use and integrate into your existing Go structs.
- **Seamless Integration**: These types work just like Go's standard types but add support for `null` values, 
  enabling cleaner and more maintainable code.
- **JSON Unmarshalling Support**: Automatically handles the unmarshalling of JSON fields, converting `null` JSON 
  values to Go's `nil` or zero values, depending on the context.
- **Minimalistic and Lightweight**: Designed to be lightweight and unobtrusive, so it won't bloat your application 
  or introduce unnecessary dependencies (only relies on the Go standard library)

### Example Usage

```go
package main

import (
    "encoding/json"
    "fmt"
    "os"
    
    "github.com/wneessen/niljson"
)

type JSONType struct {
    Bool       niljson.NilBoolean `json:"bool"`
    Float32    niljson.NilFloat32 `json:"float32,omitempty"`
    Float64    niljson.NilFloat64 `json:"float64"`
    Int        niljson.NilInt     `json:"int"`
    Int64      niljson.NilInt64   `json:"int64"`
    NullString niljson.NilString  `json:"nil"`
    String     niljson.NilString  `json:"string"`
}

func main() {
    data := []byte(`{"string":"test", "int":123, "int64": 12345678901234, "float64":0, "nil":null, "bool":true}`)
    
    var example JSONType
    if err := json.Unmarshal(data, &example); err != nil {
        fmt.Println("failed to unmarshal JSON:", err)
        os.Exit(1)
    }

    if example.Bool.NotNil() {
        fmt.Printf("Bool is: %t\n", example.Bool.Value())
    }
	if example.Float64.IsNil() {
		fmt.Println("Float 32 is NIL")
	}
	if example.Float64.NotNil() {
		fmt.Printf("Float is: %f\n", example.Float64.Value())
	}
    if !example.String.IsNil() {
        fmt.Printf("String is: %s\n", example.String.Value())
    }
}
```