578ed1ba98
Moving all of my Emacs-related files into their own directory at the root of this repository.
109 lines
3.4 KiB
EmacsLisp
109 lines
3.4 KiB
EmacsLisp
;;; bytes.el --- Working with byte values -*- lexical-binding: t -*-
|
|
;; Author: William Carroll <wpcarro@gmail.com>
|
|
|
|
;;; Commentary:
|
|
;; Functions to help with human-readable representations of byte values.
|
|
;;
|
|
;; Usage:
|
|
;; See the test cases for example usage. Or better yet, I should use a type of
|
|
;; structured documentation that would allow me to expose a view into the test
|
|
;; suite here. Is this currently possible in Elisp?
|
|
;;
|
|
;; API:
|
|
;; - serialize :: Integer -> String
|
|
;;
|
|
;; Wish list:
|
|
;; - Rounding: e.g. (bytes (* 1024 1.7)) => "2KB"
|
|
|
|
;;; Code:
|
|
|
|
;; TODO: Support -ibabyte variants like Gibibyte (GiB).
|
|
|
|
;; Ranges:
|
|
;; B: [ 0, 1e3)
|
|
;; KB: [ 1e3, 1e6)
|
|
;; MB: [ 1e6, 1e6)
|
|
;; GB: [ 1e9, 1e12)
|
|
;; TB: [1e12, 1e15)
|
|
;; PB: [1e15, 1e18)
|
|
;;
|
|
;; Note: I'm currently not support exabytes because that causes the integer to
|
|
;; overflow. I imagine a larger integer type may exist, but for now, I'll
|
|
;; treat this as a YAGNI.
|
|
|
|
(require 'prelude)
|
|
(require 'tuple)
|
|
(require 'math)
|
|
(require 'number)
|
|
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
;; Constants
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
|
|
(defconst bytes/kb (math/exp 2 10)
|
|
"Number of bytes in a kilobyte.")
|
|
|
|
(defconst bytes/mb (math/exp 2 20)
|
|
"Number of bytes in a megabytes.")
|
|
|
|
(defconst bytes/gb (math/exp 2 30)
|
|
"Number of bytes in a gigabyte.")
|
|
|
|
(defconst bytes/tb (math/exp 2 40)
|
|
"Number of bytes in a terabyte.")
|
|
|
|
(defconst bytes/pb (math/exp 2 50)
|
|
"Number of bytes in a petabyte.")
|
|
|
|
(defconst bytes/eb (math/exp 2 60)
|
|
"Number of bytes in an exabyte.")
|
|
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
;; Functions
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
|
|
(defun bytes/classify (x)
|
|
"Return unit that closest fits byte count, X."
|
|
(prelude/assert (number/whole? x))
|
|
(cond
|
|
((and (>= x 0) (< x bytes/kb)) 'byte)
|
|
((and (>= x bytes/kb) (< x bytes/mb)) 'kilobyte)
|
|
((and (>= x bytes/mb) (< x bytes/gb)) 'megabyte)
|
|
((and (>= x bytes/gb) (< x bytes/tb)) 'gigabyte)
|
|
((and (>= x bytes/tb) (< x bytes/pb)) 'terabyte)
|
|
((and (>= x bytes/pb) (< x bytes/eb)) 'petabyte)))
|
|
|
|
(defun bytes/to-string (x)
|
|
"Convert integer X into a human-readable string."
|
|
(let ((base-and-unit
|
|
(pcase (bytes/classify x)
|
|
('byte (tuple/from 1 "B"))
|
|
('kilobyte (tuple/from bytes/kb "KB"))
|
|
('megabyte (tuple/from bytes/mb "MB"))
|
|
('gigabyte (tuple/from bytes/gb "GB"))
|
|
('terabyte (tuple/from bytes/tb "TB"))
|
|
('petabyte (tuple/from bytes/pb "PB")))))
|
|
(string/format "%d%s"
|
|
(round x (tuple/first base-and-unit))
|
|
(tuple/second base-and-unit))))
|
|
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
;; Tests
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
|
|
(progn
|
|
(prelude/assert
|
|
(equal "1000B" (bytes/to-string 1000)))
|
|
(prelude/assert
|
|
(equal "2KB" (bytes/to-string (* 2 bytes/kb))))
|
|
(prelude/assert
|
|
(equal "17MB" (bytes/to-string (* 17 bytes/mb))))
|
|
(prelude/assert
|
|
(equal "419GB" (bytes/to-string (* 419 bytes/gb))))
|
|
(prelude/assert
|
|
(equal "999TB" (bytes/to-string (* 999 bytes/tb))))
|
|
(prelude/assert
|
|
(equal "2PB" (bytes/to-string (* 2 bytes/pb)))))
|
|
|
|
(provide 'bytes)
|
|
;;; bytes.el ends here
|