13.4. Character Attributes
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13.4. Character Attributes [sec_13-1-3]

13.4.1. Input Characters

Characters have no implementation-defined or [CLtL1] font and bit attributes. All characters are simple characters.

13.4.1. Input Characters

For backward compatibility, there is a class SYS::INPUT-CHARACTER representing either a character with font and bits, or a keystroke. The following functions work with objects of types CHARACTER and SYS::INPUT-CHARACTER. Note that EQL or EQUAL are equivalent to EQ on objects of type SYS::INPUT-CHARACTER.

EXT:CHAR-FONT-LIMIT = 16
The system uses only font 0.
EXT:CHAR-BITS-LIMIT = 16

Character bits:

keyvalue
:CONTROLEXT:CHAR-CONTROL-BIT
:METAEXT:CHAR-META-BIT
:SUPEREXT:CHAR-SUPER-BIT
:HYPEREXT:CHAR-HYPER-BIT
(EXT:CHAR-FONT object)
returns the font of a CHARACTER or SYS::INPUT-CHARACTER.
(EXT:CHAR-BITS object)
returns the bits of a CHARACTER or SYS::INPUT-CHARACTER.
(EXT:MAKE-CHAR char [bits [font]])
returns a new SYS::INPUT-CHARACTER, or NIL if such a character cannot be created.
(EXT:CHAR-BIT object name)
returns T if the named bit is set in object, else NIL.
(EXT:SET-CHAR-BIT object name new-value)
returns a new SYS::INPUT-CHARACTER with the named bit set or unset, depending on the BOOLEAN new-value.

Warning

SYS::INPUT-CHARACTER is not a subtype of CHARACTER.

Platform Dependent: UNIX, Win32 platforms only.
The system itself uses this SYS::INPUT-CHARACTER type only to mention special keys and Control/Alternate/Shift key status on return from (READ-CHAR EXT:*KEYBOARD-INPUT*).
These notes document CLISP version 2.49Last modified: 2010-07-07
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