You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
230 lines
8.8 KiB
230 lines
8.8 KiB
4 months ago
|
:mod:`curses.ascii` --- Utilities for ASCII characters
|
||
|
|
======================================================
|
||
|
|
|
||
|
|
.. module:: curses.ascii
|
||
|
|
:synopsis: Constants and set-membership functions for ASCII characters.
|
||
|
|
|
||
|
|
.. moduleauthor:: Eric S. Raymond <esr@thyrsus.com>
|
||
|
|
.. sectionauthor:: Eric S. Raymond <esr@thyrsus.com>
|
||
|
|
|
||
|
|
--------------
|
||
|
|
|
||
|
|
The :mod:`curses.ascii` module supplies name constants for ASCII characters and
|
||
|
|
functions to test membership in various ASCII character classes. The constants
|
||
|
|
supplied are names for control characters as follows:
|
||
|
|
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| Name | Meaning |
|
||
|
|
+==============+==============================================+
|
||
|
|
| :const:`NUL` | |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`SOH` | Start of heading, console interrupt |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`STX` | Start of text |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`ETX` | End of text |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`EOT` | End of transmission |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`ENQ` | Enquiry, goes with :const:`ACK` flow control |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`ACK` | Acknowledgement |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`BEL` | Bell |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`BS` | Backspace |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`TAB` | Tab |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`HT` | Alias for :const:`TAB`: "Horizontal tab" |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`LF` | Line feed |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`NL` | Alias for :const:`LF`: "New line" |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`VT` | Vertical tab |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`FF` | Form feed |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`CR` | Carriage return |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`SO` | Shift-out, begin alternate character set |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`SI` | Shift-in, resume default character set |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`DLE` | Data-link escape |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`DC1` | XON, for flow control |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`DC2` | Device control 2, block-mode flow control |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`DC3` | XOFF, for flow control |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`DC4` | Device control 4 |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`NAK` | Negative acknowledgement |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`SYN` | Synchronous idle |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`ETB` | End transmission block |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`CAN` | Cancel |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`EM` | End of medium |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`SUB` | Substitute |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`ESC` | Escape |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`FS` | File separator |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`GS` | Group separator |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`RS` | Record separator, block-mode terminator |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`US` | Unit separator |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`SP` | Space |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
| :const:`DEL` | Delete |
|
||
|
|
+--------------+----------------------------------------------+
|
||
|
|
|
||
|
|
Note that many of these have little practical significance in modern usage. The
|
||
|
|
mnemonics derive from teleprinter conventions that predate digital computers.
|
||
|
|
|
||
|
|
The module supplies the following functions, patterned on those in the standard
|
||
|
|
C library:
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: isalnum(c)
|
||
|
|
|
||
|
|
Checks for an ASCII alphanumeric character; it is equivalent to ``isalpha(c) or
|
||
|
|
isdigit(c)``.
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: isalpha(c)
|
||
|
|
|
||
|
|
Checks for an ASCII alphabetic character; it is equivalent to ``isupper(c) or
|
||
|
|
islower(c)``.
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: isascii(c)
|
||
|
|
|
||
|
|
Checks for a character value that fits in the 7-bit ASCII set.
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: isblank(c)
|
||
|
|
|
||
|
|
Checks for an ASCII whitespace character; space or horizontal tab.
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: iscntrl(c)
|
||
|
|
|
||
|
|
Checks for an ASCII control character (in the range 0x00 to 0x1f or 0x7f).
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: isdigit(c)
|
||
|
|
|
||
|
|
Checks for an ASCII decimal digit, ``'0'`` through ``'9'``. This is equivalent
|
||
|
|
to ``c in string.digits``.
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: isgraph(c)
|
||
|
|
|
||
|
|
Checks for ASCII any printable character except space.
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: islower(c)
|
||
|
|
|
||
|
|
Checks for an ASCII lower-case character.
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: isprint(c)
|
||
|
|
|
||
|
|
Checks for any ASCII printable character including space.
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: ispunct(c)
|
||
|
|
|
||
|
|
Checks for any printable ASCII character which is not a space or an alphanumeric
|
||
|
|
character.
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: isspace(c)
|
||
|
|
|
||
|
|
Checks for ASCII white-space characters; space, line feed, carriage return, form
|
||
|
|
feed, horizontal tab, vertical tab.
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: isupper(c)
|
||
|
|
|
||
|
|
Checks for an ASCII uppercase letter.
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: isxdigit(c)
|
||
|
|
|
||
|
|
Checks for an ASCII hexadecimal digit. This is equivalent to ``c in
|
||
|
|
string.hexdigits``.
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: isctrl(c)
|
||
|
|
|
||
|
|
Checks for an ASCII control character (ordinal values 0 to 31).
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: ismeta(c)
|
||
|
|
|
||
|
|
Checks for a non-ASCII character (ordinal values 0x80 and above).
|
||
|
|
|
||
|
|
These functions accept either integers or single-character strings; when the argument is a
|
||
|
|
string, it is first converted using the built-in function :func:`ord`.
|
||
|
|
|
||
|
|
Note that all these functions check ordinal bit values derived from the
|
||
|
|
character of the string you pass in; they do not actually know anything about
|
||
|
|
the host machine's character encoding.
|
||
|
|
|
||
|
|
The following two functions take either a single-character string or integer
|
||
|
|
byte value; they return a value of the same type.
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: ascii(c)
|
||
|
|
|
||
|
|
Return the ASCII value corresponding to the low 7 bits of *c*.
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: ctrl(c)
|
||
|
|
|
||
|
|
Return the control character corresponding to the given character (the character
|
||
|
|
bit value is bitwise-anded with 0x1f).
|
||
|
|
|
||
|
|
|
||
|
|
.. function:: alt(c)
|
||
|
|
|
||
|
|
Return the 8-bit character corresponding to the given ASCII character (the
|
||
|
|
character bit value is bitwise-ored with 0x80).
|
||
|
|
|
||
|
|
The following function takes either a single-character string or integer value;
|
||
|
|
it returns a string.
|
||
|
|
|
||
|
|
|
||
|
|
.. index::
|
||
|
|
single: ^ (caret); in curses module
|
||
|
|
single: ! (exclamation); in curses module
|
||
|
|
|
||
|
|
.. function:: unctrl(c)
|
||
|
|
|
||
|
|
Return a string representation of the ASCII character *c*. If *c* is printable,
|
||
|
|
this string is the character itself. If the character is a control character
|
||
|
|
(0x00--0x1f) the string consists of a caret (``'^'``) followed by the
|
||
|
|
corresponding uppercase letter. If the character is an ASCII delete (0x7f) the
|
||
|
|
string is ``'^?'``. If the character has its meta bit (0x80) set, the meta bit
|
||
|
|
is stripped, the preceding rules applied, and ``'!'`` prepended to the result.
|
||
|
|
|
||
|
|
|
||
|
|
.. data:: controlnames
|
||
|
|
|
||
|
|
A 33-element string array that contains the ASCII mnemonics for the thirty-two
|
||
|
|
ASCII control characters from 0 (NUL) to 0x1f (US), in order, plus the mnemonic
|
||
|
|
``SP`` for the space character.
|
||
|
|
|