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@ISPRINT[string]: Returns 1 if string is entirely composed of printable characters; 0 otherwise.

See also: @ISALNUM, @ISALPHA, @ISASCII, @ISCNTRL, @ISDIGIT, @ISPUNCT, @ISSPACE, @ISXDIGIT.

Examples:

echo %@isprint[abc]

1

set var=abc^ndef

echo %@isprint[%var]

0