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at 2026-03-10T15:11:21-07:00

Clean up docstrings and update cmucl.pot

Add tests for printing double-double special values

Make sure double-double-float NaN and infinities are printed in hex
format correctly.

 (defun write-hex-float-double (x stream)

   "Print a single- or double-float in hex format onto STREAM.

-   Float type and mantissa width are derived from the type of X."

+  Float type and mantissa width are derived from the type of X."

   (multiple-value-bind (mantissa-bits suffix-char min-c-exp)

       (etypecase x

         (single-float (values (1- (float-digits 1f0)) #\f (- vm:single-float-bias)))

 #+double-double

 (defun write-hex-float-double-double (x stream)

-  "Print a double-double-float in hex format onto STREAM.

-   Reconstructs the full significand from hi and lo components

-   using exact integer arithmetic before formatting."

+  "Print a double-double-float in hex format onto STREAM."

   (let* ((hi  (kernel:double-double-hi x))

          (lo  (kernel:double-double-lo x)))

     ;; Print the sign, but not for NaN since float-sign is unreliable there.

 ;;; Writes a float value (single, double, or double-double) in hex

 ;;; format to a stream, defaulting to *standard-output*.

 (defun write-hex-float (x &optional (stream *standard-output*))

-  "Write float X to STREAM in C-style hex format. STREAM defaults to *standard-output*.

+  "Write float X to STREAM in C-style hex format. STREAM defaults to

+  *standard-output*.

    single-float        => 0x<mantissa>p<exp>f

    double-float        => 0x<mantissa>p<exp>

 ;;;

 ;;; Function that can be used in a FORMAT ~/

 (defun format-hex-float (stream x colonp atsignp &rest args)

-  "Format function for use with ~/package:format-hex-float/.

+  "Format function for use with ~/ext:format-hex-float/.

   Ignores colon modifier.  At-sign modifier forces a leading + sign on

-  non-negative values. Example: (format t \"~@/ext:format-hex-float/\"

-  3.0d0) => +0x1.8p+1"

+  non-negative values.

+

+  Example: (format t \"~@/ext:format-hex-float/\" 3.0d0) => +0x1.8p+1"

   (declare (ignore colonp args))

   (when (and atsignp

              (not (float-nan-p x))

 (defun read-hex-float-from-string (s &key (start 0) end)

   "Read a C-style hex float from string S.

   START and END bound the region to read (default: entire string).

+  Signals HEX-FLOAT-PARSE-ERROR on malformed input.

+

   Returns two values: the float and the index of the first character

-  not consumed.  Signals HEX-FLOAT-PARSE-ERROR on malformed input."

+ not consumed."

   (with-input-from-string (stream s :start start :end end)

     (values (read-hex-float-from-stream stream)

             (file-position stream))))

 ;;; READ-HEX-FLOAT -- Public

 ;;;

 ;;; Read a C-style hex float number from either a string or a stream.

-(defun ext:read-hex-float (stream-or-string &key (start 0) end)

+(defun read-hex-float (stream-or-string &key (start 0) end)

   "Read a C-style hex float from STREAM-OR-STRING.

   If a string, START and END bound the region to read.  When reading

   from a string, returns two values: the float and the index of the

   (assert-equal "0x1.fffffffffffff8p-1w"

                 (ext:float-to-hex-string (- 1.0w0 (scale-float 1.0w0 -54)))))

+(define-test write-double-double-special

+  (assert-equal "0x1.0p+infw"

+                (ext:float-to-hex-string (float ext:double-float-positive-infinity 1w0)))

+  (assert-equal "-0x1.0p+infw"

+                (ext:float-to-hex-string (float ext:double-float-negative-infinity 1w0)))

+  (assert-equal "0x0.0p+nanw"

+                (ext:float-to-hex-string

+                  (ext:with-float-traps-masked (:invalid)

+                    (- (float ext:double-float-positive-infinity 1w0)

+                       (float ext:double-float-positive-infinity 1w0))))))

+

 ;;; ---- read-hex-float tests ------------------------------------------------

Raymond Toy pushed to branch issue-480-double-double-hex-printer at cmucl / cmucl

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