Common Helpers

Overview

The utils package provides common helper functions for type checking, string manipulation, and goroutine control.

API Reference

IsNil[T any](v T) bool

Checks if a value is nil. Supports interface, pointer, slice, map, channel, function, and chan types.

var s *string = nil
if utils.IsNil(s) {
    fmt.Println("Value is nil")
}

// Works with generics
var arr []int = nil
utils.IsNil(arr) // true

IsDigits(s string) bool

Checks if a string consists entirely of digits (0-9).

utils.IsDigits("12345") // true
utils.IsDigits("12a45") // false
utils.IsDigits("")      // true (empty string)

DelayDo(d time.Duration, fn func())

Executes a function after a delay. This is a blocking operation.

utils.DelayDo(500*time.Millisecond, func() {
    fmt.Println("Delayed execution")
})

PPrint(obj interface{})

Prints an object in a formatted way. Alias for PPrettyPrint.

utils.PPrint(myStruct)

Hold()

Blocks the current goroutine indefinitely. Use for debugging or keeping the program running.

utils.Hold() // Blocks forever

Example

package main

import (
	"fmt"
	"time"

	"github.com/leoheung/go-patterns/utils"
)

func main() {
	// Check for nil values
	var ptr *int = nil
	fmt.Printf("ptr is nil: %v\n", utils.IsNil(ptr))

	var slice []string = nil
	fmt.Printf("slice is nil: %v\n", utils.IsNil(slice))

	// Check if string is all digits
	fmt.Printf("\"123\" is digits: %v\n", utils.IsDigits("123"))
	fmt.Printf("\"12a\" is digits: %v\n", utils.IsDigits("12a"))

	// Delayed execution
	fmt.Println("Starting delayed task...")
	utils.DelayDo(1*time.Second, func() {
		fmt.Println("Delayed task executed!")
	})
	fmt.Println("After delay")
}

Notes

• IsNil uses reflection and handles various types correctly
• IsDigits returns true for empty strings
• DelayDo blocks until the delay completes
• Hold() creates a deadlock intentionally, use only for debugging