iterutil

README

iterutil

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iterutil is a small and handy Go utility package that makes your loops more elegant and ✨functional✨. It’s designed to solve the problem where defer statements inside standard for loops only execute when the entire function returns!

Usage

🔂 Times

Times executes a callback function a specified number of times.

iterutil.Times(5, func (i int) {
    fmt.Println(i) // prints 0 through 4
})

📈 Ranges

Ranges iterates from start to end (exclusive) and applies the callback function to each index. It supports both ascending and descending ranges.

iterutil.Ranges(2, 5, func (i int) {
    fmt.Println(i) // prints 2, 3, 4
})

iterutil.Ranges(5, 2, func (i int) {
    fmt.Println(i) // prints 5, 4, 3
})

🏃 StepRanges

StepRanges lets you customize the step size, giving you full control over iteration intervals — forward or backward.

iterutil.StepRanges(0, 10, 2, func(i int) {
    fmt.Println(i) // prints 0, 2, 4, 6, 8
})

iterutil.StepRanges(10, 0, -3, func (i int) {
    fmt.Println(i) // prints 10, 7, 4, 1
})

Why Use It?

In traditional for loops, any defer statements execute only when the enclosing function returns — not after each iteration.

With iterutil, you can use closures to scope each iteration and ensure defer runs right when you expect it to. 🎯

Example:

iterutil.Times(3, func (i int) {
    defer fmt.Println("deferred", i)
    fmt.Println("running", i)
})

Output:

running 0
deferred 0
running 1
deferred 1
running 2
deferred 2

License

This project is licensed under the MIT License.

Documentation

Index

• func Ranges(start, end int, fn func(i int))
• func StepRanges(start, end, step int, fn func(i int))
• func Times(count int, fn func(i int))

Functions

func Ranges

func Ranges(start, end int, fn func(i int))

Ranges iterates from 'start' to 'end' (exclusive) and applies 'fn' to each index. Used to eliminate deferred execution under standard for loops.

func StepRanges

func StepRanges(start, end, step int, fn func(i int))

StepRanges iterates from 'start' to 'end' using a step size and applies 'fn' to each index. Used to eliminate deferred execution under standard for loops.

func Times

func Times(count int, fn func(i int))

Times executes the function 'fn' exactly 'count' times. Used to eliminate deferred execution under standard for loops.