Size

[mgi]

Hi, I'm using this library and needed a way to obtain the size of a binary class. This is what those patches do.

You can define how the byte size is calculated in define-binary-type. For example:

(define-binary-type unsigned-integer (bytes bits-per-byte)
  (:reader (in)
    (loop with value = 0
       for low-bit downfrom (* bits-per-byte (1- bytes)) to 0 by bits-per-byte do
         (setf (ldb (byte bits-per-byte low-bit) value) (read-byte in))
       finally (return value)))
  (:writer (out value)
    (loop for low-bit downfrom (* bits-per-byte (1- bytes)) to 0 by bits-per-byte
	  do (write-byte (ldb (byte bits-per-byte low-bit) value) out)))
  (:size () bytes))
(define-binary-type u2 () (unsigned-integer :bytes 2 :bits-per-byte 8))

then define a binary class that use it:

(define-binary-class foo () ((a u2) (b u2)))

and finally obtain the byte size of such object:

(object-size 'foo)

[mgi]

ping?

[mgi]

pong?