lisp/progmodes/hideif.el (hif-tokenize): Understand non-decimal floats.

2 files changed, 14 insertions, 6 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 51d5de2f3be..30e76c013b7 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,5 +1,8 @@
 2014-03-20  Juanma Barranquero  <lekktu@gmail.com>
 
+        * progmodes/hideif.el (hif-string-to-number): New function.
+        (hif-tokenize): Use it to understand non-decimal floats.
+
         * emacs-lisp/cl-extra.el (cl--map-overlays): Remove obsolete code.
 
         * skeleton.el (skeleton-autowrap): Mark as obsolete.  Doc fix.
diff --git a/lisp/progmodes/hideif.el b/lisp/progmodes/hideif.el
index 39ad676f593..bcb46592465 100644
--- a/lisp/progmodes/hideif.el
+++ b/lisp/progmodes/hideif.el
@@ -407,6 +407,14 @@ that form should be displayed.")
 
 (defconst hif-string-literal-regexp  "\\(\"\\(?:[^\"\\]\\|\\\\.\\)*\"\\)")
 
+(defun hif-string-to-number (string &optional base)
+  "Like `string-to-number', but it understands non-decimal floats."
+  (if (or (not base) (= base 10))
+      (string-to-number string base)
+    (let* ((parts (split-string string "\\." t "[ \t]+"))
+           (frac (cadr parts))
+           (quot (expt (* base 1.0) (length frac))))
+      (/ (string-to-number (concat (car parts) frac) base) quot))))
 
 (defun hif-tokenize (start end)
   "Separate string between START and END into a list of tokens."
@@ -433,15 +441,12 @@ that form should be displayed.")
                    ;; TODO:
                    ;; 1. postfix 'l', 'll', 'ul' and 'ull'
                    ;; 2. floating number formats
-                   ;; 3. hexadecimal/octal floats
-                   ;; 4. 098 is interpreted as octal conversion error
-                   ;; FIXME: string-to-number does not convert hex floats
+                   ;; 3. 098 is interpreted as octal conversion error
                    (if (string-match "0x\\([0-9a-fA-F]+\\.?[0-9a-fA-F]*\\)"
                                      token)
-                       (string-to-number (match-string 1 token) 16)) ;; hex
-                   ;; FIXME: string-to-number does not convert octal floats
+                       (hif-string-to-number (match-string 1 token) 16)) ;; hex
                    (if (string-match "\\`0[0-9]+\\(\\.[0-9]+\\)?\\'" token)
-                       (string-to-number token 8)) ;; octal
+                       (hif-string-to-number token 8)) ;; octal
                    (if (string-match "\\`[1-9][0-9]*\\(\\.[0-9]+\\)?\\'"
                                      token)
                        (string-to-number token)) ;; decimal