Function dedent

Lib/textwrap.py:416–444

Remove any common leading whitespace from every line in `text`. This can be used to make triple-quoted strings line up with the left edge of the display, while still presenting them in the source code in indented form. Note that tabs and spaces are both treated as whitespace, but t

(text)

# -- Loosely related functionality -------------------------------------

def dedent(text):
    """Remove any common leading whitespace from every line in `text`.

    This can be used to make triple-quoted strings line up with the left
    edge of the display, while still presenting them in the source code
    in indented form.

    Note that tabs and spaces are both treated as whitespace, but they
    are not equal: the lines "  hello" and "\\thello" are
    considered to have no common leading whitespace.

    Entirely blank lines are normalized to a newline character.
    """
    try:
        lines = text.split('\n')
    except (AttributeError, TypeError):
        msg = f'expected str object, not {type(text).__qualname__!r}'
        raise TypeError(msg) from None

    # Get length of leading whitespace, inspired by ``os.path.commonprefix()``.
    non_blank_lines = [l for l in lines if l and not l.isspace()]
    l1 = min(non_blank_lines, default='')
    l2 = max(non_blank_lines, default='')
    margin = 0
    for margin, c in enumerate(l1):
        if c != l2[margin] or c not in ' \t':
            break

    return '\n'.join([l[margin:] if not l.isspace() else '' for l in lines])


def indent(text, prefix, predicate=None):