strlistutils

🧰 Utility functions for working with []string in Go.
📦 Documentation: https://pkg.go.dev/github.com/shinagawa-web/strlistutils

Why

Developers repeatedly re-implement the same []string routines (dedup, trim, filter). This package centralizes those patterns with clear behavior and tests, so teams can:

• avoid ad-hoc snippets scattered across services,
• keep behavior consistent and reviewable,
• get predictable performance without external deps.

Features

• 🧹 RemoveDuplicates — remove duplicate strings
• ✂️ TrimEach — trim whitespace from each element
• ❌ FilterEmpty — remove empty strings
• 🔁 Map — apply a function to each element
• 🧪 Filter — filter elements by a predicate
• 🔗 Join — join elements with a separator
• ↩️ Reverse — reverse the list

Installation

go get github.com/shinagawa-web/strlistutils@v0.3.0

🔒 It is recommended to pin a version to avoid unexpected breaking changes.

Install

go get github.com/shinagawa-web/strlistutils@v0.3.0

Pin a version to avoid accidental breakage.

Quick Start

package main

import (
	"fmt"

	"github.com/shinagawa-web/strlistutils"
)

func main() {
	input := []string{" a ", "b", "a", " ", "c"}

	out := strlistutils.RemoveDuplicates(
		strlistutils.FilterEmpty(
			strlistutils.TrimEach(input),
		),
	)
	fmt.Println(out) // ["a", "b", "c"]
}

➡️ For more examples, see GoDoc or examples

API

The package intentionally keeps a small surface area:

Function	Behavior
RemoveDuplicates([]string) []string	Deduplicate while preserving first appearance order.
TrimEach([]string) []string	Trim leading/trailing spaces from each element.
FilterEmpty([]string) []string	Remove empty strings.
Map([]string, func(string) string) []string	Apply a mapper to each element.
Filter([]string, func(string) bool) []string	Keep elements that satisfy the predicate.
Join([]string, string) string	Join with a separator.
Reverse([]string) []string	Reverse the order.	([GitHub][1])

Performance and Reliability

• No allocations beyond what the operation requires (e.g., dedup uses a set and preserves order).
• Benchmarks and fuzz tests are included in the repository to keep regressions visible in CI.

Versioning Policy

This library aims to be stable. Minor releases may add functions; breaking changes will bump the major version. Pin a tag in go.mod when adopting.

Real-world use

Typical use cases include CSV cleaning, environment variable parsing, and HTTP input normalization. A short write-up on the motivation and design is available on the project site/blog.

What's Included

Test Coverage

• Unit tests for all functions
• Benchmark tests
• Fuzz tests
• GitHub Actions CI
• Codecov integration

Usage Examples

• Example code in examples/ directory
• Real-world use case: cleaning CSV input

License

MIT