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char/=

char/=

type: function (subr) 
location: built-in
source file: xlstr.c
Common LISP compatible: yes
supported on: all machines

SYNTAX

(char/= <char1> <charN> ... )
        <char1>         -       a character expression
        <charN>         -       character expression(s) to compare

DESCRIPTION

The CHAR/= (character-NOT-EQUAL) function takes one or more character arguments. It checks to see if all the character arguments are different values. T is returned if the arguments are of different ASCII value. In the case of two arguments, this has the effect of testing if <char1> is not equal to <char2>. This test is case sensitive - the character #\a is different (and of greater ASCII value) than #\A.

EXAMPLES

(char/= #\a #\b)                        ; returns T
(char/= #\a #\b #\c)                    ; returns T
(char/= #\a #\a)                        ; returns NIL 
(char/= #\a #\b #\b)                    ; returns NIL
(char/= #\A #\a)                        ; returns T
(char/= #\a #\A)                        ; returns T

NOTE: Be sure that the CHAR/= function is properly typed in. The '/' is a forward slash. It is possible to mistakenly type a '\' (backslash). This is especially easy because the character mechanism is '#\a'. If you do use the backslash, no error will be reported because backslash is the single escape character and the LISP reader will evaluate 'CHAR\=' as 'CHAR='. No error will be reported, but the sense of the test is reversed.


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