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Regular Expresion in python does not match in non greedy in python

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Regular expressions (regex or regexp) are a powerful tool for pattern matching and text manipulation. In Python, the re module provides support for regular expressions. By default, regular expressions in Python are greedy, meaning they try to match as much as possible. However, there are cases where you might want to perform non-greedy matching, also known as lazy or minimal matching. This tutorial will guide you through using non-greedy matching in Python regular expressions with code examples.
Before diving into non-greedy matching, let's briefly review the basics of regular expressions in Python.
By default, regular expressions are greedy, meaning they match as much as possible.
To perform non-greedy matching, you can use the ? modifier after the quantifier. The ? makes the quantifier non-greedy, causing it to match as little as possible.
In this example, the ? after \d+ makes the pattern match the smallest sequence of digits possible. So, instead of matching the entire string "123", it matches only the first digit "1".
Let's consider a more practical example. Suppose you have a string with HTML tags, and you want to extract the content between the first pair of p tags.
In this example, (.*?) is a non-greedy group that matches the content between the first pair of p tags. The ? makes the * quantifier non-greedy.
Non-greedy matching in Python regular expressions is a useful feature when you want to match the smallest possible portion of a string. By using the ? modifier after quantifiers, you can control the greediness of the regular expression. This can be particularly handy in scenarios where you want to extract specific content from a larger text.
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Before diving into non-greedy matching, let's briefly review the basics of regular expressions in Python.
By default, regular expressions are greedy, meaning they match as much as possible.
To perform non-greedy matching, you can use the ? modifier after the quantifier. The ? makes the quantifier non-greedy, causing it to match as little as possible.
In this example, the ? after \d+ makes the pattern match the smallest sequence of digits possible. So, instead of matching the entire string "123", it matches only the first digit "1".
Let's consider a more practical example. Suppose you have a string with HTML tags, and you want to extract the content between the first pair of p tags.
In this example, (.*?) is a non-greedy group that matches the content between the first pair of p tags. The ? makes the * quantifier non-greedy.
Non-greedy matching in Python regular expressions is a useful feature when you want to match the smallest possible portion of a string. By using the ? modifier after quantifiers, you can control the greediness of the regular expression. This can be particularly handy in scenarios where you want to extract specific content from a larger text.
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