;; TODO: (eof-object? )

(symbol? 'x)
(symbol? 5)
(symbol? #t)
(symbol? '())
(symbol? '(a . b))

(number? 'x)
(number? 5)
(number? #t)
(number? '())
(number? '(a . b))

(char? 'x)
(char? 5)
(char? #t)
(char? '())
(char? '(a . b))

(string? 'x)
(string? 5)
(string? #t)
(string? '())
(string? '(a . b))

(null? 'x)
(null? 5)
(null? #t)
(null? '())
(null? '(a . b))

(pair? 'x)
(pair? 5)
(pair? #t)
(pair? '())
(pair? '(a . b))

(boolean? #t)
(boolean? #f)
(boolean? '())

(procedure? (lambda (i) i))
(procedure? procedure?)
(procedure? 5)
