yarl vs. parsel

Each part of a URL, which includes the scheme, user, password, host, port, path, query, and fragment, can be accessed via their designated properties. When a URL is manipulated, it creates a new URL object, and any strings passed into the constructor or modification functions are automatically encoded to achieve a standard format. Standard properties return values that are percent-decoded, while the raw_ variants are used when you need the encoded strings. For a version of the URL that is easier for humans to read, the .human_repr() method can be utilized. The yarl library offers binary wheels on PyPI for various operating systems, including Linux, Windows, and MacOS. If you need to install yarl on systems like Alpine Linux, which do not meet manylinux standards because they lack glibc, you will have to compile the library from the source using the provided tarball. This compilation requires that you have a C compiler and the appropriate Python headers installed on your system. It's crucial to note that the uncompiled, pure-Python version of yarl tends to be significantly slower than its compiled counterpart. However, users of PyPy will find that it generally uses a pure-Python implementation, meaning it does not suffer from these performance discrepancies. Consequently, PyPy users can rely on the library to deliver consistent behavior across different environments, ensuring a uniform experience no matter where it is run.

Parsel is a Python library that is distributed under the BSD license, designed to simplify the process of extracting and manipulating data from HTML and XML documents by utilizing XPath and CSS selectors, with the added flexibility of incorporating regular expressions. To get started, one must create a selector object that targets the specific HTML or XML content for analysis. Once this is established, users can leverage either CSS or XPath expressions to pinpoint the desired elements. CSS acts as a styling language for HTML, offering selectors that connect styles to specific HTML elements, while XPath is employed to choose nodes within XML documents and can also be effectively used with HTML. While both CSS and XPath are viable options, CSS generally offers improved readability, whereas XPath possesses functionalities that may not be attainable through CSS alone. Built upon the lxml library, parsel selectors include certain EXSLT extensions and come equipped with pre-registered namespaces for use in XPath queries. Additionally, parsel selectors facilitate the chaining of selectors, allowing users to primarily select elements by class with CSS and seamlessly switch to XPath when necessary, thereby providing enhanced flexibility in data extraction tasks. This combination of features renders parsel an invaluable resource for developers engaged in web data manipulation. Moreover, the ability to toggle between two powerful selection methods ensures that users can optimize their data extraction strategies according to the complexity of their tasks.