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regex

This modules contains all of the regex-related names and utilites.

escape_markup(text)

Escapes any potential markup to avoid double-parsing.

Use this when treating already parsed markup.

Source code in pytermgui/regex.py 
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def escape_markup(text: str) -> str:
    """Escapes any potential markup to avoid double-parsing.

    Use this when treating already parsed markup.
    """

    def _escape(mtch: Match) -> str:
        full, *_ = mtch.groups()

        return full.replace("[", r"\[")

    return RE_MARKUP.sub(_escape, text)

has_open_sequence(text) cached

Figures out if the given text has any unclosed ANSI sequences.

It supports standard SGR (\x1b[1mHello), OSC (\x1b[30;2ST\x1b\\) and Kitty APC codes (_Garguments;hex_data\x1b\\). It also recognizes incorrect syntax; it only considers a tag closed when it is using the right closing sequence, e.g. m or H for SGR, \x1b\\ for OSC and APC types.

Parameters:

Name Type Description Default
text str

The text to test.

 required

Returns:

Type Description
bool

True if there is at least one tag that hasn't been closed, False otherwise.
Source code in pytermgui/regex.py 
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@lru_cache(maxsize=1024)
def has_open_sequence(text: str) -> bool:
    """Figures out if the given text has any unclosed ANSI sequences.

    It supports standard SGR (`\\x1b[1mHello`), OSC (`\\x1b[30;2ST\\x1b\\\\`) and Kitty APC codes
    (`\x1b_Garguments;hex_data\\x1b\\\\`). It also recognizes incorrect syntax; it only considers
    a tag closed when it is using the right closing sequence, e.g. `m` or `H` for SGR, `\\x1b\\\\`
    for OSC and APC types.

    Args:
        text: The text to test.

    Returns:
        True if there is at least one tag that hasn't been closed, False otherwise.
    """

    is_osc = False
    is_sgr = False
    is_apc = False

    open_count = 0
    sequence = ""

    for char in text:
        if char == "\x1b":
            open_count += 1
            sequence += char
            continue

        if len(sequence) == 0:
            continue

        # Ignore OSC and APC closers as new openers
        if char == "\\" and sequence[-1] == "\x1b":
            open_count -= 1

        is_osc = is_osc or sequence[:2] == "\x1b]"
        is_sgr = is_sgr or sequence[:2] == "\x1b["
        is_apc = is_apc or sequence[:3] == "\x1b_G"

        sequence += char
        if (is_osc or is_apc) and sequence[-2:] == "\x1b\\":
            sequence = ""
            open_count -= 1

        elif is_sgr and char in {"m", "H"}:
            sequence = ""
            open_count -= 1

    return len(sequence) != 0 or open_count != 0

real_length(text) cached

Gets the display-length of text.

This length means no ANSI sequences are counted. This method is a convenience wrapper for len(strip_ansi(text)).

Parameters:

Name Type Description Default
text str

The text to calculate the length of.

 required

Returns:

Type Description
int

The display-length of text.
Source code in pytermgui/regex.py 
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@lru_cache(maxsize=None)
def real_length(text: str) -> int:
    """Gets the display-length of text.

    This length means no ANSI sequences are counted. This method is a convenience wrapper
    for `len(strip_ansi(text))`.

    Args:
        text: The text to calculate the length of.

    Returns:
        The display-length of text.
    """

    return max(wcswidth(strip_ansi(text)), 0)

strip_ansi(text) cached

Removes ANSI sequences from text.

Parameters:

Name Type Description Default
text str

A string or bytes object containing 0 or more ANSI sequences.

 required

Returns:

Type Description
str

The text without any ANSI sequences.
Source code in pytermgui/regex.py 
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@lru_cache()
def strip_ansi(text: str) -> str:
    """Removes ANSI sequences from text.

    Args:
        text: A string or bytes object containing 0 or more ANSI sequences.

    Returns:
        The text without any ANSI sequences.
    """

    if hasattr(text, "plain"):
        return text.plain  # type: ignore

    return RE_ANSI.sub("", text)

strip_markup(text) cached

Removes markup tags from text.

Parameters:

Name Type Description Default
text str

A string or bytes object containing 0 or more markup tags.

 required

Returns:

Type Description
str

The text without any markup tags.
Source code in pytermgui/regex.py 
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@lru_cache()
def strip_markup(text: str) -> str:
    """Removes markup tags from text.

    Args:
        text: A string or bytes object containing 0 or more markup tags.

    Returns:
        The text without any markup tags.
    """

    return RE_MARKUP.sub("", text)