[nongnu] elpa/julia-mode b5f5983 346/352: Indent lines after hanging operator even if previous line contains # (#115)

[ELPA Syncer]

branch: elpa/julia-mode
commit b5f5983d2b232c8bba4c5eff75cccdb787c19d98
Author: Adam B <adam_gpg@thebeckmeyers.xyz>
Commit: GitHub <noreply@github.com>

    Indent lines after hanging operator even if previous line contains # (#115)
    
    * General refactor and improvements
    
    These are changes unrelated to #15 that just make the code a bit more
    readable. This commit should be reviewed separately.
    
    Since the julia group was declared with a :prefix of julia- all of
    these customization variables will be in the julia group anyway. Also,
    since julia-mode didn't declare it's group, an anonymous julia-mode
    group was getting created for faces.
    
    * Move around definitions to get code byte-compiling cleanly
    
    * Indent lines after hanging operator even if previous line contains #
    
    Because the previous implementation used a regex to detect whether the
    hanging operator was in a comment or not, it did not detect hanging
    operators following a # in a string.
    
    Fixes #19
    
    * Add comment explaining automatic adding to latest defgroup
---
 julia-mode-tests.el |  36 +++++++++-
 julia-mode.el       | 194 ++++++++++++++++++++++++++--------------------------
 2 files changed, 130 insertions(+), 100 deletions(-)

diff --git a/julia-mode-tests.el b/julia-mode-tests.el
index 94d46bb..f348821 100644
--- a/julia-mode-tests.el
+++ b/julia-mode-tests.el
@@ -88,6 +88,8 @@ matching line or end of match if END is non-nil.  Optional 
ARG is passed to FUN.
                                       (point-at-bol)))
                            ,to)))))
 
+;;; indent tests
+
 (ert-deftest julia--test-indent-if ()
   "We should indent inside if bodies."
   (julia--should-indent
@@ -452,6 +454,36 @@ end"
 end")
   )
 
+(ert-deftest julia--test-indent-hanging ()
+  "Test indentation for line following a hanging operator."
+  (julia--should-indent
+   "
+f(x) =
+x*
+x"
+   "
+f(x) =
+    x*
+    x")
+  (julia--should-indent
+   "
+a = \"#\" |>
+identity"
+   "
+a = \"#\" |>
+    identity")
+  ;; make sure we don't interpret a hanging operator in a comment as
+  ;; an actual hanging operator for indentation
+  (julia--should-indent
+   "
+a = \"#\" # |>
+identity"
+   "
+a = \"#\" # |>
+identity"))
+
+;;; font-lock tests
+
 (ert-deftest julia--test-symbol-font-locking-at-bol ()
   "Symbols get font-locked at beginning or line."
   (julia--should-font-lock
@@ -598,8 +630,8 @@ end")
   "Point moves to beginning of multi-line assignment function."
   (julia--should-move-point
     "f(x)=
-x*
-x" 'beginning-of-defun "\\*\nx" 1))
+    x*
+    x" 'beginning-of-defun "x$" 1))
 
 (ert-deftest julia--test-beginning-of-defun-assn-3 ()
   "Point moves to beginning of multi-line assignment function adjoining
diff --git a/julia-mode.el b/julia-mode.el
index dedf966..0230ff6 100644
--- a/julia-mode.el
+++ b/julia-mode.el
@@ -45,22 +45,19 @@
   "Major mode for the julia programming language."
   :group 'languages
   :prefix "julia-")
+;; all custom variables are automatically added to the most recent defgroup
 
 (defcustom julia-indent-offset 4
   "Number of spaces per indentation level."
-  :type 'integer
-  :group 'julia)
+  :type 'integer)
 
 (defface julia-macro-face
   '((t :inherit font-lock-preprocessor-face))
-  "Face for Julia macro invocations."
-  :group 'julia-mode)
+  "Face for Julia macro invocations.")
 
 (defface julia-quoted-symbol-face
   '((t :inherit font-lock-constant-face))
-  "Face for quoted Julia symbols, e.g. :foo."
-  :group 'julia-mode)
-
+  "Face for quoted Julia symbols, e.g. :foo.")
 
 ;;;###autoload
 (add-to-list 'auto-mode-alist '("\\.jl\\'" . julia-mode))
@@ -119,68 +116,68 @@
 
 (defconst julia-hanging-operator-regexp
   ;; taken from julia-parser.scm
-  (concat "^[^#\n]+ "
-          (regexp-opt
-           '( ;; conditional
-             "?"
-             ;; assignment
-             "=" ":=" "+=" "-=" "*=" "/=" "//=" ".//=" ".*=" "./=" "\\=" ".\\="
-             "^=" ".^=" "÷=" ".÷=" "%=" ".%=" "|=" "&=" "$=" "=>" "<<=" ">>="
-             ">>>=" "~" ".+=" ".-="
-             ;; arrow
-             "--" "-->" "←" "→" "↔" "↚" "↛" "↠" "↣" "↦" "↮" "⇎" "⇏" "⇒" "⇔" "⇴"
-             "⇶" "⇷" "⇸" "⇹" "⇺" "⇻" "⇼" "⇽" "⇾" "⇿" "⟵" "⟶" "⟷" "⟷" "⟹"
-             "⟺" "⟻" "⟼" "⟽" "⟾" "⟿" "⤀" "⤁" "⤂" "⤃" "⤄" "⤅" "⤆" "⤇" "⤌"
-             "⤍" "⤎" "⤏" "⤐" "⤑" "⤔" "⤕" "⤖" "⤗" "⤘" "⤝" "⤞" "⤟" "⤠" "⥄" "⥅"
-             "⥆" "⥇" "⥈" "⥊" "⥋" "⥎" "⥐" "⥒" "⥓" "⥖" "⥗" "⥚" "⥛" "⥞" "⥟" "⥢"
-             "⥤" "⥦" "⥧" "⥨" "⥩" "⥪" "⥫" "⥬" "⥭" "⥰" "⧴" "⬱" "⬰" "⬲" "⬳" "⬴"
-             "⬵" "⬶" "⬷" "⬸" "⬹" "⬺" "⬻" "⬼" "⬽" "⬾" "⬿" "⭀" "⭁" "⭂" "⭃" "⭄"
-             "⭇" "⭈" "⭉" "⭊" "⭋" "⭌" "￩" "￫"
-             ;; or and and
-             "&&" "||"
-             ;; comparison
-             ">" "<" ">=" "≥" "<=" "≤" "==" "===" "≡" "!=" "≠" "!==" "≢" ".>"
-             ".<" ".>=" ".≥" ".<=" ".≤" ".==" ".!=" ".≠" ".=" ".!" "<:" ">:" 
"∈"
-             "∉" "∋" "∌" "⊆" "⊈" "⊂" "⊄" "⊊" "∝" "∊" "∍" "∥" "∦" "∷" "∺" "∻" 
"∽"
-             "∾" "≁" "≃" "≄" "≅" "≆" "≇" "≈" "≉" "≊" "≋" "≌" "≍" "≎" "≐" "≑" 
"≒"
-             "≓" "≔" "≕" "≖" "≗" "≘" "≙" "≚" "≛" "≜" "≝" "≞" "≟" "≣" "≦" "≧" 
"≨"
-             "≩" "≪" "≫" "≬" "≭" "≮" "≯" "≰" "≱" "≲" "≳" "≴" "≵" "≶" "≷" "≸" 
"≹"
-             "≺" "≻" "≼" "≽" "≾" "≿" "⊀" "⊁" "⊃" "⊅" "⊇" "⊉" "⊋" "⊏" "⊐" "⊑" 
"⊒"
-             "⊜" "⊩" "⊬" "⊮" "⊰" "⊱" "⊲" "⊳" "⊴" "⊵" "⊶" "⊷" "⋍" "⋐" "⋑" "⋕" 
"⋖"
-             "⋗" "⋘" "⋙" "⋚" "⋛" "⋜" "⋝" "⋞" "⋟" "⋠" "⋡" "⋢" "⋣" "⋤" "⋥" "⋦" 
"⋧"
-             "⋨" "⋩" "⋪" "⋫" "⋬" "⋭" "⋲" "⋳" "⋴" "⋵" "⋶" "⋷" "⋸" "⋹" "⋺" "⋻" 
"⋼"
-             "⋽" "⋾" "⋿" "⟈" "⟉" "⟒" "⦷" "⧀" "⧁" "⧡" "⧣" "⧤" "⧥" "⩦" "⩧" "⩪" 
"⩫"
-             "⩬" "⩭" "⩮" "⩯" "⩰" "⩱" "⩲" "⩳" "⩴" "⩵" "⩶" "⩷" "⩸" "⩹" "⩺" "⩻" 
"⩼"
-             "⩽" "⩾" "⩿" "⪀" "⪁" "⪂" "⪃" "⪄" "⪅" "⪆" "⪇" "⪈" "⪉" "⪊" "⪋" "⪌" 
"⪍"
-             "⪎" "⪏" "⪐" "⪑" "⪒" "⪓" "⪔" "⪕" "⪖" "⪗" "⪘" "⪙" "⪚" "⪛" "⪜" "⪝" 
"⪞"
-             "⪟" "⪠" "⪡" "⪢" "⪣" "⪤" "⪥" "⪦" "⪧" "⪨" "⪩" "⪪" "⪫" "⪬" "⪭" "⪮" 
"⪯"
-             "⪰" "⪱" "⪲" "⪳" "⪴" "⪵" "⪶" "⪷" "⪸" "⪹" "⪺" "⪻" "⪼" "⪽" "⪾" "⪿" 
"⫀"
-             "⫁" "⫂" "⫃" "⫄" "⫅" "⫆" "⫇" "⫈" "⫉" "⫊" "⫋" "⫌" "⫍" "⫎" "⫏" "⫐" 
"⫑"
-             "⫒" "⫓" "⫔" "⫕" "⫖" "⫗" "⫘" "⫙" "⫷" "⫸" "⫹" "⫺" "⊢" "⊣"
-             ;; pipe, colon
-             "|>" "<|" ":" ".."
-             ;; plus
-             "+" "-" "⊕" "⊖" "⊞" "⊟" ".+" ".-" "++" "|" "∪" "∨" "$" "⊔" "±" "∓"
-             "∔" "∸" "≂" "≏" "⊎" "⊻" "⊽" "⋎" "⋓" "⧺" "⧻" "⨈" "⨢" "⨣" "⨤" "⨥" 
"⨦"
-             "⨧" "⨨" "⨩" "⨪" "⨫" "⨬" "⨭" "⨮" "⨹" "⨺" "⩁" "⩂" "⩅" "⩊" "⩌" "⩏" 
"⩐"
-             "⩒" "⩔" "⩖" "⩗" "⩛" "⩝" "⩡" "⩢" "⩣"
-             ;; bitshift
-             "<<" ">>" ">>>" ".<<" ".>>" ".>>>"
-             ;; times
-             "*" "/" "./" "÷" ".÷" "%" "⋅" "∘" "×" ".%" ".*" "\\"
-             ".\\" "&" "∩" "∧" "⊗" "⊘" "⊙" "⊚" "⊛" "⊠" "⊡" "⊓" "∗" "∙" "∤" "⅋"
-             "≀" "⊼" "⋄" "⋆" "⋇" "⋉" "⋊" "⋋" "⋌" "⋏" "⋒" "⟑" "⦸" "⦼" "⦾" "⦿" 
"⧶"
-             "⧷" "⨇" "⨰" "⨱" "⨲" "⨳" "⨴" "⨵" "⨶" "⨷" "⨸" "⨻" "⨼" "⨽" "⩀" "⩃" 
"⩄"
-             "⩋" "⩍" "⩎" "⩑" "⩓" "⩕" "⩘" "⩚" "⩜" "⩞" "⩟" "⩠" "⫛" "⊍" "▷" "⨝" 
"⟕"
-             "⟖" "⟗"
-             ;; rational
-             "//" ".//"
-             ;; power
-             "^" ".^" "↑" "↓" "⇵" "⟰" "⟱" "⤈" "⤉" "⤊" "⤋" "⤒" "⤓" "⥉" "⥌" "⥍"
-             "⥏" "⥑" "⥔" "⥕" "⥘" "⥙" "⥜" "⥝" "⥠" "⥡" "⥣" "⥥" "⥮" "⥯" "￪" "￬"
-             ;; decl, dot
-             "::" "."))
-          (regexp-opt '(" #" " \n" "#" "\n"))))
+  (rx (or
+       ;; conditional
+       "?"
+       ;; assignment
+       "=" ":=" "+=" "-=" "*=" "/=" "//=" ".//=" ".*=" "./=" "\\=" ".\\="
+       "^=" ".^=" "÷=" ".÷=" "%=" ".%=" "|=" "&=" "$=" "=>" "<<=" ">>="
+       ">>>=" "~" ".+=" ".-="
+       ;; arrow
+       "--" "-->" "←" "→" "↔" "↚" "↛" "↠" "↣" "↦" "↮" "⇎" "⇏" "⇒" "⇔" "⇴"
+       "⇶" "⇷" "⇸" "⇹" "⇺" "⇻" "⇼" "⇽" "⇾" "⇿" "⟵" "⟶" "⟷" "⟷" "⟹"
+       "⟺" "⟻" "⟼" "⟽" "⟾" "⟿" "⤀" "⤁" "⤂" "⤃" "⤄" "⤅" "⤆" "⤇" "⤌"
+       "⤍" "⤎" "⤏" "⤐" "⤑" "⤔" "⤕" "⤖" "⤗" "⤘" "⤝" "⤞" "⤟" "⤠" "⥄" "⥅"
+       "⥆" "⥇" "⥈" "⥊" "⥋" "⥎" "⥐" "⥒" "⥓" "⥖" "⥗" "⥚" "⥛" "⥞" "⥟" "⥢"
+       "⥤" "⥦" "⥧" "⥨" "⥩" "⥪" "⥫" "⥬" "⥭" "⥰" "⧴" "⬱" "⬰" "⬲" "⬳" "⬴"
+       "⬵" "⬶" "⬷" "⬸" "⬹" "⬺" "⬻" "⬼" "⬽" "⬾" "⬿" "⭀" "⭁" "⭂" "⭃" "⭄"
+       "⭇" "⭈" "⭉" "⭊" "⭋" "⭌" "￩" "￫"
+       ;; or and and
+       "&&" "||"
+       ;; comparison
+       ">" "<" ">=" "≥" "<=" "≤" "==" "===" "≡" "!=" "≠" "!==" "≢" ".>"
+       ".<" ".>=" ".≥" ".<=" ".≤" ".==" ".!=" ".≠" ".=" ".!" "<:" ">:" "∈"
+       "∉" "∋" "∌" "⊆" "⊈" "⊂" "⊄" "⊊" "∝" "∊" "∍" "∥" "∦" "∷" "∺" "∻" "∽"
+       "∾" "≁" "≃" "≄" "≅" "≆" "≇" "≈" "≉" "≊" "≋" "≌" "≍" "≎" "≐" "≑" "≒"
+       "≓" "≔" "≕" "≖" "≗" "≘" "≙" "≚" "≛" "≜" "≝" "≞" "≟" "≣" "≦" "≧" "≨"
+       "≩" "≪" "≫" "≬" "≭" "≮" "≯" "≰" "≱" "≲" "≳" "≴" "≵" "≶" "≷" "≸" "≹"
+       "≺" "≻" "≼" "≽" "≾" "≿" "⊀" "⊁" "⊃" "⊅" "⊇" "⊉" "⊋" "⊏" "⊐" "⊑" "⊒"
+       "⊜" "⊩" "⊬" "⊮" "⊰" "⊱" "⊲" "⊳" "⊴" "⊵" "⊶" "⊷" "⋍" "⋐" "⋑" "⋕" "⋖"
+       "⋗" "⋘" "⋙" "⋚" "⋛" "⋜" "⋝" "⋞" "⋟" "⋠" "⋡" "⋢" "⋣" "⋤" "⋥" "⋦" "⋧"
+       "⋨" "⋩" "⋪" "⋫" "⋬" "⋭" "⋲" "⋳" "⋴" "⋵" "⋶" "⋷" "⋸" "⋹" "⋺" "⋻" "⋼"
+       "⋽" "⋾" "⋿" "⟈" "⟉" "⟒" "⦷" "⧀" "⧁" "⧡" "⧣" "⧤" "⧥" "⩦" "⩧" "⩪" "⩫"
+       "⩬" "⩭" "⩮" "⩯" "⩰" "⩱" "⩲" "⩳" "⩴" "⩵" "⩶" "⩷" "⩸" "⩹" "⩺" "⩻" "⩼"
+       "⩽" "⩾" "⩿" "⪀" "⪁" "⪂" "⪃" "⪄" "⪅" "⪆" "⪇" "⪈" "⪉" "⪊" "⪋" "⪌" "⪍"
+       "⪎" "⪏" "⪐" "⪑" "⪒" "⪓" "⪔" "⪕" "⪖" "⪗" "⪘" "⪙" "⪚" "⪛" "⪜" "⪝" "⪞"
+       "⪟" "⪠" "⪡" "⪢" "⪣" "⪤" "⪥" "⪦" "⪧" "⪨" "⪩" "⪪" "⪫" "⪬" "⪭" "⪮" "⪯"
+       "⪰" "⪱" "⪲" "⪳" "⪴" "⪵" "⪶" "⪷" "⪸" "⪹" "⪺" "⪻" "⪼" "⪽" "⪾" "⪿" "⫀"
+       "⫁" "⫂" "⫃" "⫄" "⫅" "⫆" "⫇" "⫈" "⫉" "⫊" "⫋" "⫌" "⫍" "⫎" "⫏" "⫐" "⫑"
+       "⫒" "⫓" "⫔" "⫕" "⫖" "⫗" "⫘" "⫙" "⫷" "⫸" "⫹" "⫺" "⊢" "⊣"
+       ;; pipe, colon
+       "|>" "<|" ":" ".."
+       ;; plus
+       "+" "-" "⊕" "⊖" "⊞" "⊟" ".+" ".-" "++" "|" "∪" "∨" "$" "⊔" "±" "∓"
+       "∔" "∸" "≂" "≏" "⊎" "⊻" "⊽" "⋎" "⋓" "⧺" "⧻" "⨈" "⨢" "⨣" "⨤" "⨥" "⨦"
+       "⨧" "⨨" "⨩" "⨪" "⨫" "⨬" "⨭" "⨮" "⨹" "⨺" "⩁" "⩂" "⩅" "⩊" "⩌" "⩏" "⩐"
+       "⩒" "⩔" "⩖" "⩗" "⩛" "⩝" "⩡" "⩢" "⩣"
+       ;; bitshift
+       "<<" ">>" ">>>" ".<<" ".>>" ".>>>"
+       ;; times
+       "*" "/" "./" "÷" ".÷" "%" "⋅" "∘" "×" ".%" ".*" "\\"
+       ".\\" "&" "∩" "∧" "⊗" "⊘" "⊙" "⊚" "⊛" "⊠" "⊡" "⊓" "∗" "∙" "∤" "⅋"
+       "≀" "⊼" "⋄" "⋆" "⋇" "⋉" "⋊" "⋋" "⋌" "⋏" "⋒" "⟑" "⦸" "⦼" "⦾" "⦿" "⧶"
+       "⧷" "⨇" "⨰" "⨱" "⨲" "⨳" "⨴" "⨵" "⨶" "⨷" "⨸" "⨻" "⨼" "⨽" "⩀" "⩃" "⩄"
+       "⩋" "⩍" "⩎" "⩑" "⩓" "⩕" "⩘" "⩚" "⩜" "⩞" "⩟" "⩠" "⫛" "⊍" "▷" "⨝" "⟕"
+       "⟖" "⟗"
+       ;; rational
+       "//" ".//"
+       ;; power
+       "^" ".^" "↑" "↓" "⇵" "⟰" "⟱" "⤈" "⤉" "⤊" "⤋" "⤒" "⤓" "⥉" "⥌" "⥍"
+       "⥏" "⥑" "⥔" "⥕" "⥘" "⥙" "⥜" "⥝" "⥠" "⥡" "⥣" "⥥" "⥮" "⥯" "￪" "￬"
+       ;; decl, dot
+       "::" ".")
+      (* blank)
+      (or eol ?#)))
 
 (defconst julia-unquote-regex
   "\\(\\s(\\|\\s-\\|-\\|[,%=<>\\+*/?&|!\\^~\\\\;:]\\|^\\)\\($[a-zA-Z0-9_]+\\)")
@@ -302,6 +299,21 @@
 (defconst julia-block-end-keywords
   (list "end" "else" "elseif" "catch" "finally"))
 
+(defsubst julia-syntax-comment-or-string-p (&optional syntax-ppss)
+  "Return non-nil if SYNTAX-PPSS is inside string or comment."
+  (nth 8 (or syntax-ppss (syntax-ppss))))
+
+(defun julia-in-comment (&optional syntax-ppss)
+  "Return non-nil if point is inside a comment using SYNTAX-PPSS.
+Handles both single-line and multi-line comments."
+  (nth 4 (or syntax-ppss (syntax-ppss))))
+
+(defun julia-in-string (&optional syntax-ppss)
+  "Return non-nil if point is inside a string using SYNTAX-PPSS.
+Note this is Emacs' notion of what is highlighted as a string.
+As a result, it is true inside \"foo\", `foo` and 'f'."
+  (nth 3 (or syntax-ppss (syntax-ppss))))
+
 (defconst julia-syntax-propertize-function
   (syntax-propertize-rules
    ;; triple-quoted strings are a single string rather than 3
@@ -312,7 +324,8 @@
     (0 (ignore (julia-syntax-stringify))))
    ;; backslash acts as an operator if it's not inside a string
    ("\\\\"
-    (0 (unless (nth 3 (save-excursion (syntax-ppss (match-beginning 0))))
+    (0 (unless (julia-in-string
+                (save-excursion (syntax-ppss (match-beginning 0))))
          (string-to-syntax "."))))
    (julia-char-regex
     ;; treat ' in 'c' as string-delimiter
@@ -344,17 +357,6 @@
      ;; of overlapping triple-quotes with first escaped
      ((backward-char 2)))))
 
-(defun julia-in-comment (&optional syntax-ppss)
-  "Return non-nil if point is inside a comment using SYNTAX-PPSS.
-Handles both single-line and multi-line comments."
-  (nth 4 (or syntax-ppss (syntax-ppss))))
-
-(defun julia-in-string (&optional syntax-ppss)
-  "Return non-nil if point is inside a string using SYNTAX-PPSS.
-Note this is Emacs' notion of what is highlighted as a string.
-As a result, it is true inside \"foo\", `foo` and 'f'."
-  (nth 3 (or syntax-ppss (syntax-ppss))))
-
 (defun julia-in-brackets ()
   "Return non-nil if point is inside square brackets."
   (let ((start-pos (point))
@@ -365,7 +367,7 @@ As a result, it is true inside \"foo\", `foo` and 'f'."
 
       (while (< (point) start-pos)
         ;; Don't count [ or ] inside strings, characters or comments.
-        (unless (or (julia-in-string) (julia-in-comment))
+        (unless (julia-syntax-comment-or-string-p)
 
           (when (looking-at (rx "["))
             (cl-incf open-count))
@@ -381,7 +383,7 @@ As a result, it is true inside \"foo\", `foo` and 'f'."
   "Return the word at point if it matches any keyword in KW-LIST.
 KW-LIST is a list of strings.  The word at point is not considered
 a keyword if used as a field name, X.word, or quoted, :word."
-  (and (or (= (point) 1)
+  (and (or (bobp)
           (and (not (equal (char-before (point)) ?.))
                (not (equal (char-before (point)) ?:))))
        (not (looking-at "("))           ; handle "function(" when on (
@@ -411,7 +413,7 @@ symbol, gives up when this is not true."
       (while (and (not done) (< (point-min) (point)))
         (julia-safe-backward-sexp)
         (cond
-         ((looking-at (rx (or "import" "export" "using")))
+         ((looking-at (regexp-opt (list "import" "export" "using")))
           (setf done (point)))
          ((looking-at (rx (group (* (or word (syntax symbol)))) (0+ space) 
":"))
           (if module
@@ -452,12 +454,6 @@ Do not move back beyond MIN."
           (goto-char pos)
           (+ julia-indent-offset (current-indentation))))))
 
-(defsubst julia--safe-backward-char ()
-  "Move back one character, but don't error if we're at the
-beginning of the buffer."
-  (unless (eq (point) (point-min))
-    (backward-char)))
-
 (defcustom julia-max-block-lookback 20000
   "When indenting, don't look back more than this many characters
 to see if there are unclosed blocks.
@@ -465,8 +461,7 @@ to see if there are unclosed blocks.
 This variable has a small effect on indent performance if set
 too high, but stops indenting in the middle of long blocks if set
 too low."
-  :type 'integer
-  :group 'julia)
+  :type 'integer)
 
 (defun julia-paren-indent ()
   "Return the column of the text following the innermost
@@ -528,6 +523,12 @@ the (possibly narrowed) buffer, so there is nowhere else 
to go."
          (t
           (throw 'result 0)))))))
 
+(defun julia--hanging-operator-p ()
+  "Return t if current line ends with a hanging operator."
+  (and (re-search-forward julia-hanging-operator-regexp (line-end-position) t)
+       (not (julia-syntax-comment-or-string-p
+             (save-excursion (syntax-ppss (match-beginning 0)))))))
+
 (defun julia-indent-hanging ()
   "Calculate indentation for lines that follow \"hanging\"
 operators (operators that end the previous line) as defined in
@@ -540,9 +541,9 @@ only comments."
     (save-excursion
       (when (> (julia-prev-line-skip-blank-or-comment) 0)
         (setq prev-indent (current-indentation))
-        (when (looking-at-p julia-hanging-operator-regexp)
+        (when (julia--hanging-operator-p)
           (if (and (> (julia-prev-line-skip-blank-or-comment) 0)
-                   (looking-at-p julia-hanging-operator-regexp))
+                   (julia--hanging-operator-p))
               ;; two preceding hanging operators => indent same as line
               ;; above
               prev-indent
@@ -620,10 +621,6 @@ TYPE can be `comment', `string' or `paren'."
      ((nth 8 ppss) (if (nth 4 ppss) 'comment 'string))
      ((nth 1 ppss) 'paren))))
 
-(defsubst julia-syntax-comment-or-string-p (&optional syntax-ppss)
-  "Return non-nil if SYNTAX-PPSS is inside string or comment."
-  (nth 8 (or syntax-ppss (syntax-ppss))))
-
 (defun julia-looking-at-beginning-of-defun (&optional syntax-ppss)
   "Check if point is at `beginning-of-defun' using SYNTAX-PPSS."
   (and (not (julia-syntax-comment-or-string-p (or syntax-ppss (syntax-ppss))))
@@ -746,6 +743,7 @@ Return nil if point is not in a function, otherwise point."
 ;;;###autoload
 (define-derived-mode julia-mode prog-mode "Julia"
   "Major mode for editing julia code."
+  :group 'julia
   (set-syntax-table julia-mode-syntax-table)
   (setq-local comment-start "# ")
   (setq-local comment-start-skip "#+\\s-*")