How to reverse expressions in XPath?

To reverse expression in XPath the not() function can be used which reverses any expression passed to it.

This is useful for creative negative predicates that are vital in many HTML parsing tasks. See this interactive example:

<!-- select only product data and ignore advertisements--> <article> <h1>Product Details:</h1> <div>price: 199</div> <div class="advertisement">Buy today?</div> <div>year: 2023</div> </article>

Above, we can use not() function to filter out special HTML elements like advertisements.

Question tagged: XPath

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