jevandezande/file_iter

A Swiss Army knife iterator for files (or any iterator of strings)

File Iter

A Swiss Army knife iterator for files (or any iterator of strings)

• Strips lines
• Keeps track of the current line: current_line
• Keeps track of the line number: position
  • Specify position if entering in the middle of a file: FileIter(f, position=10)
• Peek at the next line: peek()
• Jump ahead n lines jump(n)
• Check if empty: isempty()
• Filter out unimportant lines:
  • Always filter: FileIter(f, filter_func=is_data)
  • Filter only single next(): filter_next(filter_func)

>>> def is_data(line: str) -> bool:
...    return len(line) > 0 and (line[0] != "#")
>>> my_iter = FileIter(
...     ["Hello", "", "# comment", "World", "How", "are", "you?"],
...     filter_func=is_data
... )
>>> next(my_iter)
'Hello'
>>> my_iter.peek()  # peek does not respect filter_func
''
>>> next(my_iter)  # skips "" and "# comment"
'World'
>>> my_iter.position
3
>>> my_iter.current_line
'World'
>>> my_iter.jump(3)  # jump does not respect filter_func
'you?'
>>> my_iter.position
6
>>> my_iter.isempty()
True
>>> my_iter.peek(default="default")
'default'

Opening and closing the file can be performed with a context manager, this even works on gzipped files!

document.txt

Hello

# comment
World

>>> with FileIterContextManager("document.txt", filter_func=is_data) as file_iter:
...     for line in file_iter:
...         print(line, file_iter.position)
Hello 0
World 3

Credits

This package was created with Cookiecutter and the jevandezande/poetry-cookiecutter project template.