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ACL2 Characters

ACL2 Characters

ACL2 accepts 256 distinct characters, which are the characters obtained by applying the function code-char to each integer from 0 to 255. Among these, Common Lisp designates certain ones as *standard-characters*, namely those of the form (code-char n) where n is from 33 to 126, together with #\Newline and #\Space. The actual standard characters may be viewed by evaluating the constant expression *standard-chars*.

The standard character constants are written by writing a hash mark followed by a backslash (#\) followed by the character.

The function characterp recognizes characters. For more details, See characters .