[elpa] master 61fd27e: num3-mode: support binary numbers

[Michal Nazarewicz]

branch: master
commit 61fd27e2b8cff1e73ced50fe800a1779526ccced
Author: Michal Nazarewicz <address@hidden>
Commit: Michal Nazarewicz <address@hidden>

    num3-mode: support binary numbers
    
    It maks more sense for binary numbers to be grouped in nibbles rather
    than threes (which is the default for decimal numbers) so if number
    starts with 0b or #b, treat it as a binary number and group in fours.
    
    Grouping in eights (i.e., a full byte) would also make sense but
    piggy-backing on hexadecimal number support is much easier. :P
    
    * /packages/num3-mode/num3-mode.el (num3--number-re): Add alternative
    for matching binary numbers.
    (num3-mode): Document that binary numbers are also supported plus
    some other minor changes.
---
 packages/num3-mode/num3-mode.el | 43 +++++++++++++++++++++++++----------------
 1 file changed, 26 insertions(+), 17 deletions(-)

diff --git a/packages/num3-mode/num3-mode.el b/packages/num3-mode/num3-mode.el
index d4f12e0..a43c16c 100644
--- a/packages/num3-mode/num3-mode.el
+++ b/packages/num3-mode/num3-mode.el
@@ -40,8 +40,7 @@
 
 (defgroup num3 nil
   "Num3 is a minor mode that makes long numbers more readable by
-highlighting groups of decimal digits or 4 hex digits when
-font-lock is on."
+highlighting groups of digits in a number."
   :group 'text)
 
 (defcustom num3-group-size 3
@@ -70,24 +69,29 @@ addition to any other font-lock highlighting."
 (define-minor-mode num3-mode
   "Toggle num3 minor mode in the current buffer.
 Num3 minor mode makes long numbers more readable by highlighting
-groups of digits when font-lock mode is on.
+groups of digits when font-lock mode is enabled.
 
 If a number is longer than `num3-threshold', the mode will split
 it into a group of `num3-group-size' (if number is decimal) or
-4 (if number is hexadecimal) digits.  Hexadecimal number is
-detected as one starting with 0x, 0X or #.
+four (if number is hexadecimal or binary) digits.
 
-With decimal numbers, fractions are recognised as well and
-grouped from the beginning rathar then from end.  For instance,
-with group size of 3, a number \"12345.12345\" will be split into
-groups as follows: \"12|345.123|45\".  Fractions without integer
-part are also recognised, eg. \".12345\".
+Hexadecimal numbers are recognised by \"0x\" or \"#x\"
+prefix (case insensitive) and binary numbers by \"0b\" or \"#b\"
+prefix.  (There is no special handling for octal numbers –
+starting with \"0o\" or \"#o\" – and instead they are handled
+like decimal numbers).
 
-The groups are highlighted alternately using `num3-face-odd' and
+Decimal fractions are recognised as well and grouped from the
+beginning rathar then the end.  For instance, with group size of
+three, a number \"12345.12345\" will be split into groups as
+follows: \"12|345.123|45\".  Fractions without integer part are
+also recognised, eg. \".12345\".
+
+Groups are highlighted alternately using `num3-face-odd' and
 `num3-face-even' faces.  `num3-face-odd' face (which is empty by
-default) is the one used for the group closest to the decimal point,
-ie. groups are counted starting with one outwards from the (place
-where) decimal point (would be) is."
+default) is the one used for the group closest to the decimal
+point, i.e. groups are counted starting with one outwards from
+the (place where) decimal point (would be) is."
   nil " num3" nil
   (if num3-mode
       (unless (assoc 'num3--matcher font-lock-keywords)
@@ -100,11 +104,16 @@ where) decimal point (would be) is."
 (define-globalized-minor-mode global-num3-mode num3-mode num3-mode)
 
 (defconst num3--number-re
+  ;; Hexadecimal and binary are both using the first capture group because we
+  ;; group them both in four-digit groups.  There’s no explicit support for
+  ;; octal numbers because we just use logic for a decimal number, i.e. the 
same
+  ;; grouping.
   (concat "[0#][xX]\\([[:xdigit:]]+\\)"       ; 1 = hexadecimal
-        "\\|\\(?1:\\b\\(?:[0-9]+[a-fA-F]\\|"  ; 1 = hexadecimal
+       "\\|[0#][bB]\\(?1:[01]+\\)"            ; 1 = binary
+       "\\|\\(?1:\\b\\(?:[0-9]+[a-fA-F]\\|"   ; 1 = hexadecimal w/o prefix
                  "[a-fA-F]+[0-9]\\)[[:xdigit:]]*\\b\\)"
-        "\\|\\([0-9]+\\)"                     ; 2 = decimal
-        "\\|\\.\\([0-9]+\\)"))                ; 3 = fraction
+       "\\|\\([0-9]+\\)"                      ; 2 = decimal
+       "\\|\\.\\([0-9]+\\)"))                 ; 3 = fraction
 
 (defun num3--matcher (lim)
   "Function used as a font-lock-keywoard handler used in `num3-mode'.