How to Perform re.sub() on Arrays of Strings in Python While Retaining Formatting

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The Problem: Retaining Formatting in Text Segments

Imagine you have an array of strings that represents parts of a paragraph, where each element contains formatted text (like HTML <span> tags). You want to identify specific keywords within these strings and append annotations to them, while keeping the formatting intact. Performing simple substitutions won't suffice, as we risk losing the original structure of the text.

Example Input:

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Expected Output:

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This illustrates our challenge: we want to modify specific keywords while ensuring the formatting (i.e., the separation of strings) remains the same.

The Solution: Annotating with Preserved Formatting

To tackle this problem, we can follow these steps:

Step 1: Create a Function to Track Initial Segment Lengths

First, we must keep track of the original lengths of each string segment. This information is essential for reconstructing the array after we apply our substitutions.

[[See Video to Reveal this Text or Code Snippet]]

Step 2: Define the Annotation Function

Next, we define an annotate function that utilizes regular expressions to find keywords and apply the necessary annotations.

[[See Video to Reveal this Text or Code Snippet]]

Step 3: Execute the Replacement & Reconstruct the Segments

Finally, we apply the substitutions and utilize our recorded lengths to reconstruct the original array structure.

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Example with an Annotations Map

Here’s how to define your keyword annotation map and test the function:

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Sample Output

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Conclusion

Manipulating arrays of strings in Python while retaining formatting can be challenging, but with careful tracking of original segment lengths and the right use of regex, it is entirely possible. The methods discussed in this blog will help you efficiently apply transformations to your text segments without losing their structure.

Feel free to experiment with the provided functions and adapt the code snippets to your specific scenarios. Happy coding!