Enum Rel 

pub enum Rel {
    Alternate,
    Author,
    Bookmark,
    External,
    Help,
    License,
    Next,
    Nofollow,
    Noopener,
    Noreferrer,
    Prev,
    Search,
    Tag,
}

The rel attribute values for link relationships.

Purpose

Defines the relationship between the current document and the linked resource, providing semantic meaning for links and enabling special browser behaviors.

Usage Context

• Used with: <a>, <area>, <link>, <form> elements
• Multiple values: Can be space-separated (e.g., “noopener noreferrer”)
• SEO impact: Values like nofollow affect search engine crawling

Valid Values

• Alternate: Alternate representation of the document
• Author: Link to the document’s author
• Bookmark: Permalink for the nearest ancestor section
• External: Link to a different website
• Help: Link to context-sensitive help
• License: Link to copyright/license information
• Next: Next document in a sequence
• Nofollow: Do not follow this link for SEO purposes
• Noopener: Prevents window.opener access (security)
• Noreferrer: Don’t send referer header (privacy)
• Prev: Previous document in a sequence
• Search: Link to a search tool
• Tag: Tag/keyword for the current document

Example

use ironhtml_attributes::{AttributeValue, Rel};
let rel = Rel::Noopener;
assert_eq!(rel.to_attr_value(), "noopener");

<a href="https://external.com" rel="external nofollow">External Site</a>
<a href="/help" rel="help">Help Documentation</a>
<link rel="alternate" href="/feed.xml" type="application/rss+xml">
<a href="https://example.com" target="_blank" rel="noopener noreferrer">Safe Link</a>

WHATWG Specification

• Link types
• The rel attribute

Variants

Alternate

Indicates an alternate representation of the current document, such as translations, RSS feeds, or print versions.

Author

Link to information about the author of the document.

Bookmark

Provides a permalink to the nearest ancestor section.

External

Indicates the link references a resource on a different site.

Help

Link to context-sensitive help information.

License

Link to copyright, license, or legal information for the document.

Next

Indicates the next document in a sequence (pagination, slideshows).

Nofollow

Instructs search engines not to follow this link for ranking purposes.

Noopener

Prevents the new browsing context from accessing window.opener. Critical security feature for target="_blank" links.

Noreferrer

Prevents the browser from sending the Referer header. Enhances privacy.

Prev

Indicates the previous document in a sequence (pagination, slideshows).

Search

Link to a search tool or interface for the current document.

Tag

Indicates the link represents a tag or keyword for the current document.

Trait Implementations

impl AttributeValue for Rel

fn to_attr_value(&self) -> Cow<'static, str>

Convert to the attribute value string.

impl Clone for Rel

fn clone(&self) -> Rel

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Rel

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for Rel

fn eq(&self, other: &Rel) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for Rel

impl Eq for Rel

impl StructuralPartialEq for Rel