Module translator 

CSS-to-XPath translation with ::text and ::attr() pseudo-element support.

This module provides the translation layer between CSS selectors and XPath expressions, including support for the Scrapy/parsel-compatible pseudo-elements ::text and ::attr(ATTR_NAME).

Background

Python scrapling (via cssselect) translates every CSS selector to an XPath expression, which lxml then evaluates against the DOM. In Rust, the scraper crate matches CSS selectors natively — no XPath needed.

This module exists for three reasons:

1. Pseudo-element parsing — ::text and ::attr(name) must be stripped before CSS matching and applied as post-processing. The CssQuery type handles this.

2. CSS→XPath conversion — the css_to_xpath() function provides feature parity with the Python API for users who need XPath strings (e.g. for generate_xpath_selector()).

3. Caching — translations are LRU-cached (capacity 256) since the same selectors are typically used repeatedly.

Pseudo-elements

Pseudo-element	XPath suffix	Meaning
::text	/text()	Select text node children
::attr(href)	/@href	Select the href attribute value

Examples

use scrapling::translator::{CssQuery, css_to_xpath};

// Parse pseudo-elements from a CSS selector
let q = CssQuery::parse("div.content::text").unwrap();
assert_eq!(q.css(), "div.content");
assert!(q.is_text());

let q2 = CssQuery::parse("a.link::attr(href)").unwrap();
assert_eq!(q2.css(), "a.link");
assert_eq!(q2.attribute(), Some("href"));

// Translate CSS to XPath
let xpath = css_to_xpath("div.content::text").unwrap();
assert!(xpath.ends_with("/text()"));

Structs

CssQuery

A parsed CSS selector with any pseudo-element extracted.

Enums

PseudoElement

The pseudo-element extracted from a CSS selector.

Functions

css_to_xpath

Translate a CSS selector to an XPath expression.