Python Script to Remove Empty Lines and Comment-Only Lines from Text

python: remove empty lines or lines with only comment in an input text of multiple command lines with comments

To remove empty lines or lines that contain only comments from an input text of multiple command lines, you can use Python to process the text. Here's a simple script that reads the input text, processes it, and outputs the cleaned text:

def remove_empty_and_comment_lines(input_text):
    # Split the input text into lines
    lines = input_text.split('\n')
    
    # Initialize a list to hold the cleaned lines
    cleaned_lines = []
    
    # Iterate over each line
    for line in lines:
        # Strip leading and trailing whitespace
        stripped_line = line.strip()
        
        # Check if the line is not empty and does not start with a comment
        if stripped_line and not stripped_line.startswith('#'):
            cleaned_lines.append(line)
    
    # Join the cleaned lines back into a single string
    cleaned_text = '\n'.join(cleaned_lines)
    
    return cleaned_text

# Example usage
input_text = """
# This is a comment
command1
# Another comment

command2
# Yet another comment
"""

cleaned_text = remove_empty_and_comment_lines(input_text)
print(cleaned_text)

In this script:

1. The remove_empty_and_comment_lines function takes an input text as a string.
2. It splits the input text into individual lines.
3. It iterates over each line, stripping leading and trailing whitespace.
4. It checks if the stripped line is not empty and does not start with a comment (#).
5. If the line is valid, it adds it to the cleaned_lines list.
6. Finally, it joins the cleaned lines back into a single string and returns it.

When you run the example usage, the output will be:

command1
command2

This script effectively removes empty lines and lines that contain only comments from the input text.