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531 string-flipcase
string-flip case string &key (start 0) (end nil) Function
The function string-flip case returns a copy of string, with uppercase alphabetic
characters replaced by the corresponding lowercase characters, and
with lowercase alphabetic characters replaced by the corresponding uppercase
characters.
string is a string or an object that can be coerced to a string. See the
function string, page 502.
The keywords let you select portions of the string argument for case changing.
These keyword arguments must be non-negative integer indices into
the string array. The result is always the same length as string, however.
:start Specifies the position within string from which to begin case changing
(counting from 0). Default is 0, the first character in the
string. :start must be ::;; :end.
:end Specifies the position within string of the first character beyond the
end of the case changing operation. Default is nil, that is, the
operation continues to the end of the string.
Examples:
(string-flipcase "a sTrANGe UsE OF CaPitalS")
=> "A StRangE uSe of cApITAls"
(string-flipcase 'symbol) => "symbol"
(string-flipcase 'symbol :start 2 :end 4) => "SYmbOL"
(string-flipcase "End" :start 2) => "EnD"
(string-flipcase "STRing") => "strING"
The destructive version of string-flipcase is the function:
nstring-flipcase
For a table of related items: See the section "String Conversion" in Symbolics
Common Lisp: Language Concepts.
I
zl:string-flipcase string &optional (from 0) to (copy-p t) Function
This function reverses the alphabetic case in its argument: it changes uppercase
alphabetic characters to lowercase and lowercase characters to uppercase.
The effect on the original argument depends on the value of
copy-p: if copy-p is not nil, a copy of string is returned; this is the default;
if copy-p is nil, string itself is modified and returned.
string is a string or an object that can be coerced to a string. See the
function string, page 502.
from is the index in string at which to begin exchanging the case of