#### 22.4.17 *print-base*, *print-radix* [Variable] ¶

#### Value Type:: ¶

*print-base*—a radix. *print-radix*—a generalized boolean.

#### Initial Value:: ¶

The initial value of *print-base* is `10`. The initial value of *print-radix* is false.

#### Description:: ¶

*print-base* and *print-radix* control the printing of rationals. The value of *print-base* is called the current output base .

The value of *print-base* is the radix in which the printer will print rationals. For radices above `10`, letters of the alphabet are used to represent digits above `9`.

If the value of *print-radix* is true, the printer will print a radix specifier to indicate the radix in which it is printing a rational number. The radix specifier is always printed using lowercase letters. If *print-base* is `2`, `8`, or `16`, then the radix specifier used is `#b`, `#o`, or `#x`, respectively. For integers, base ten is indicated by a trailing decimal point instead of a leading radix specifier; for ratios, `#10r` is used.

#### Examples:: ¶

     (let ((*print-base* 24.) (*print-radix* t))
       (print 23.))
     |>  #24rN
    ⇒  23
     (setq *print-base* 10) ⇒  10
     (setq *print-radix* nil) ⇒  NIL
     (dotimes (i 35)
        (let ((*print-base* (+ i 2)))           ;print the decimal number 40
          (write 40)                            ;in each base from 2 to 36
          (if (zerop (mod i 10)) (terpri) (format t " "))))
     |>  101000
     |>  1111 220 130 104 55 50 44 40 37 34
     |>  31 2C 2A 28 26 24 22 20 1J 1I
     |>  1H 1G 1F 1E 1D 1C 1B 1A 19 18
     |>  17 16 15 14
    ⇒  NIL
     (dolist (pb '(2 3 8 10 16))
        (let ((*print-radix* t)                 ;print the integer 10 and
              (*print-base* pb))                ;the ratio 1/10 in bases 2,
         (format t "~&~S  ~S~
     |>  #b1010  #b1/1010
     |>  #3r101  #3r1/101
     |>  #o12  #o1/12
     |>  10.  #10r1/10
     |>  #xA  #x1/A
    ⇒  NIL

#### Affected By:: ¶

Might be bound by format, and write, write-to-string.

#### See Also:: ¶

format [Function] , write, prin1, print, pprint, princ [Function] , write-to-string, prin1-to-string, princ-to-string [Function]