structtag

structtag is a library for parsing struct tags in Go during static analysis. It is designed to provide a simple API for parsing struct field tags in Go code. This fork focuses exclusively on reading struct tags and is not intended for modifying or rewriting them. It also drops support for accessing the options of a struct tag individually.

This project is a fork of fatih/structtag, originally created by Fatih Arslan. The primary changes in this fork are:

• struct tag values are treated as blobs, options are not treated individually,
• the API surface is minimized, just so that the functionality used by 4meepo/tagalign is provided.

---

Install

To install the package:

go get github.com/alfatraining/structtag

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Example Usage

The following example demonstrates how to parse and output struct tags using structtag:

package main

import (
	"fmt"
	"reflect"

	"github.com/alfatraining/structtag"
)

func main() {
	type Example struct {
		Field string `json:"foo,omitempty" xml:"bar"`
	}

	// Get the struct tag from the field
	tag := reflect.TypeOf(Example{}).Field(0).Tag

	// Parse the tag using structtag
	tags, err := structtag.Parse(string(tag))
	if err != nil {
		panic(err)
	}

	// Iterate over all tags
	for _, t := range tags.Tags() {
		fmt.Printf("Key: %s, Value: %v\n", t.Key, t.Value)
	}
	// Output:
	// Key: json, Value: foo,omitempty
	// Key: xml, Value: bar
}

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API Overview

Parsing Struct Tags

Use Parse to parse a struct field's tag into a Tags object:

tags, err := structtag.Parse(`json:"foo,omitempty" xml:"bar"`)
if err != nil {
    panic(err)
}

Accessing Tags

• Retrieve all tags:

  allTags := tags.Tags()

Inspecting Tags

• Key: The key of the tag (e.g., json or xml).
• Value: The value of the tag (e.g., "foo,omitempty" for json:"foo,omitempty").

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Acknowledgments

This project is based on fatih/structtag, created by Fatih Arslan. Inspiration for the style of this README was taken from tylergannon/structtag, created by Tyler Gannon.