;;; eiffel.el --- major mode for editing Eiffel files.

;; Copyright (C) 1989, 1990, 93, 94, 95, 96, 99, 2000, 01, 02, 03
;;                         Tower Technology Corporation,
;;                         Free Software Foundation,
;;                         Bob Weiner,
;;                         C. Adrian

;; Authors: 1989-1990 Stephen Omohundro, ISE and Bob Weiner
;;          1993-1996 Tower Technology Corporation
;;          1999-2003 Martin Schwenke <martin@meltin.net>
;; Maintainer: martin@meltin.net
;; Keywords: eiffel languages oop
;; Requires: font-lock, compile, easymenu, imenu

;; This file is derived from eiffel4.el from Tower Technology Corporation.
;;
;; Known bugs:
;;
;; * eif-short buffer doesn't get font locked under GNU Emacs 19.34.
;;
;; * eif-debug can hang under (at least) XEmacs 21.4.[89] in the wait
;;   loop if there is input pending (that is, if the user hits return
;;   an extra time).  Not yet tested under XEmacs 21.5.
;;
;; This file is distributed under the same terms as GNU Emacs.

;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
;; Boston, MA  02110-1301, USA

;;; Commentary:

;;  NEW VERSIONS
;;    The latest version of this mode is always available via:
;;      http://meltin.net/hacks/emacs/

;;  INSTALLATION
;;    To install, simply copy this file into a directory in your
;;    load-path and add the following two commands in your .emacs file:
;;
;;    (add-to-list 'auto-mode-alist '("\\.e\\'" . eiffel-mode))
;;    (autoload 'eiffel-mode "eiffel" "Major mode for Eiffel programs" t)
;;
;;    Note: to be sure to have always a fresh eiffel.el, you can add the
;;    "SmartEiffel/misc" directory in the emacs load-path by adding:
;;
;;    (setq load-path (cons ".../SmartEiffel/misc" load-path))

;;; History:
;;

;; Add history stuff here!!!

;;; Code:

(require 'font-lock)
(require 'compile)
(require 'easymenu)
(require 'imenu)

(defconst eiffel-version-string
  "$Id: eiffel.el,v 2.67 2003/06/14 10:41:01 martins Exp $"
  "Version string to make reporting bugs more meaningful.
Note that if this file becomes part of GNU Emacs then the file might
be changed by the Emacs maintainers without this version number
changing.  This means that if you are reporting a bug for a version
that was shipped with Emacs, you should report the Emacs version!")

(defgroup eiffel nil
  "Eiffel mode for Emacs"
  :group 'oop)

(defgroup eiffel-indent nil
  "Indentation variables in Eiffel mode"
  :prefix "eif-"
  :group 'eiffel)

(defgroup eiffel-compile nil
  "Compilation support variables in Eiffel mode"
  :prefix "eif-"
  :group 'eiffel)

(defun eif-customize ()
  "Run \\[customize-group] for the `eiffel' group."
  (interactive)
  (customize-group 'eiffel))

;; Indentation amount variables.
;;
;; The default values correspond to style used in ``Eiffel: The
;; Language''.

(defcustom eif-indent-increment 3
  "*Default indentation interval (in spaces)."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-class-level-kw-indent 0
  "*Indentation for Class level keywords.
Specified as number of `eif-indent-increments'.  See the variable
`eif-class-level-keywords-regexp'."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-extra-class-level-kw-indent 0
  "*Number of extra spaces to add to `eif-class-level-kw-indent'.
This results in the actual indentation of a class level keyword.  Can
be negative."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-class-level-comment-indent 0
  "*Indentation of comments at the beginning of a class.
Specified as number of `eif-indent-increments'."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-extra-class-level-comment-indent 0
  "*Number of spaces to add to `eif-class-level-comment-indent'.
This results in the actual indentation of a class level comment.  Can
be negative."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-inherit-level-kw-indent 2
  "*Indentation of keywords falling under the Inherit clause.
Specified as number of `eif-indent-increments'.  See the variable
`eif-inherit-level-keywords'."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-extra-inherit-level-kw-indent 0
  "*Number of spaces to add to `eif-inherit-level-kw-indent'.
This results in the actual indentation of an inherit level keyword.
Can be negative."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-feature-level-indent 1
  "*Indentation amount of features.
Specified as number of `eif-indent-increments'."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-extra-feature-level-indent 0
  "*Number of spaces to add to `eif-feature-level-indent'.
This results in the indentation of a feature.  Can be negative."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-feature-level-kw-indent 2
  "*Indentation of keywords belonging to individual features.
Specified as number of `eif-indent-increments'.  See the variable
`eif-feature-level-keywords-regexp'."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-extra-feature-level-kw-indent 0
  "*Number of spaces to add to `eif-feature-level-kw-indent'.
This results in the actual indentation of a feature level keyword.
Can be negative."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-feature-level-comment-indent 3
  "*Indentation of comments at the beginning of a feature.
Specified as number of `eif-indent-increments'."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-extra-feature-level-comment-indent 0
  "*Number of spaces to add to `eif-feature-level-comment-indent'.
This results in the actual indentation of a feature level comment.
Can be negative."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-body-comment-indent 0
  "*Indentation of comments in the body of a routine.
Specified as number of `eif-indent-increments')"
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-extra-body-comment-indent 0
  "*Number of spaces to add to `eif-body-comment-indent'.
This results in the actual indentation of a routine body comment.  Can
be negative."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-check-keyword-indent 0
  "*Extra indentation for the check clause as described in ETL.
Specified as number of `eif-indent-increments'.  Default is 0, which
is different than in ETL's 1."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-extra-check-keyword-indent 0
  "*Number of spaces to add to `eif-check-keyword-indent'.
This results in the actual indentation of a check keyword.  Can be
negative."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-rescue-keyword-indent -1
  "*Extra indentation for the rescue clause as described in ETL.
Specified as number of `eif-indent-increments'.  Default is -1."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-extra-rescue-keyword-indent 0
  "*Number of spaces to add to `eif-rescue-keyword-indent'.
This results in the actual indentation of a rescue keyword.  Can be
negative."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-then-indent 0
  "*Indentation for a `then' appearing on a line by itself.
This is as opposed to a `then' on the same line as an `if'.  Specified
as number of `eif-indent-increments'."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-extra-then-indent 0
  "*Number of spaces to add to `eif-then-indent'.
This results in the actual indentation of a `then' appearing on a line
by itself.  Can be negative."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-continuation-indent 1
  "*Extra indentation for a continued statement line.
Specified as number of `eif-indent-increments'."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-extra-continuation-indent 0
  "*Number of spaces to add to `eif-continuation-indent'.
This results in the actual indentation of a continued statement
line.  Can be negative."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-string-continuation-indent 0
  "*Extra indentation for a continued string.
Specified as number of `eif-indent-increments'."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-extra-string-continuation-indent -1
  "*Number of spaces to add to `eif-string-continuation-indent'.
This results in the actual indentation of a continued string.  Can be
negative."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-indent-string-continuations-relatively-flag t
  "*Non-nil means string continuations are indented relative to 1st character.
That is, `eif-string-continuation-indent' and
`eif-extra-string-continuation-indent' are added to position of first
character of string.  If nil, string continuations are indented
relative to indent of previous line."
  :type 'boolean
  :group 'eiffel-indent)

(defcustom eif-set-tab-width-flag t
  "*Non-nil means `tab-width' is set to `eif-indent-increment' in `eiffel-mode'."
  :type 'boolean
  :group 'eiffel-indent)

(defcustom eif-preprocessor-indent 0
  "*Indentation for lines GOBO preprocessor directives.
Specified as number of `eif-indent-increments' from left margin."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-fill-max-save 4096
  "*Maximum size of a paragraph to save before filling.
Normally \\[eif-fill-paragraph] will mark a buffer as modified even if
the fill operation does not make any changes.  If the paragraph being
filled is smaller than the value of this variable then the contents of
the paragraph will be saved for comparison with the paragraph after
the fill operation.  If they are the same, the buffer modification
state is restored.  Set this to 0 to disable this feature, or a very
big number to enable it for all paragraphs."
  :type 'integer
  :group 'eiffel-indent)

(defcustom eif-use-gnu-eiffel t
  "*If t include support for compilation using GNU Liberty Eiffel."
  :type 'boolean
  :group 'eiffel-compile)

(defcustom eif-se-command
  "se"
  "*Program to use for compiling Eiffel programs.
The default is \"se\"."
  :type 'string
  :group 'eiffel-compile)

(defcustom eif-compile-options ""
  "*Options to use for compiling Eiffel programs."
  :type 'string
  :group 'eiffel-compile)

;;
;; No user-customizable definitions below this point.
;;

;;
;; Indentation macros.
;;

(defmacro eif-class-level-kw-indent-m ()
  "Indentation amount for Class level keywords (in number of spaces)."
  '(+ (* eif-class-level-kw-indent eif-indent-increment)
      eif-extra-class-level-kw-indent))

(defmacro eif-class-level-comment-indent-m ()
  "Indentation amount for Class level comments (in number of spaces)."
  '(+ (* eif-class-level-comment-indent eif-indent-increment)
      eif-extra-class-level-comment-indent))

(defmacro eif-inherit-level-kw-indent-m ()
  "Indentation amount for Inherit level keywords (in number of spaces)."
  '(+ (* eif-inherit-level-kw-indent eif-indent-increment)
      eif-extra-inherit-level-kw-indent))

(defmacro eif-feature-level-indent-m ()
  "Indentation amount for features (in number of spaces)."
  '(+ (* eif-feature-level-indent eif-indent-increment)
      eif-extra-feature-level-indent))

(defmacro eif-feature-level-kw-indent-m ()
  "Indentation amount for Feature level keywords (in number of spaces)."
  '(+ (* eif-feature-level-kw-indent eif-indent-increment)
      eif-extra-feature-level-kw-indent))

(defmacro eif-body-comment-indent-m ()
  "Indentation amount for comments in routine bodies (in number of spaces)."
  '(+ (* eif-body-comment-indent eif-indent-increment)
      eif-extra-body-comment-indent))

(defmacro eif-feature-level-comment-indent-m ()
  "Indentation amount for Feature level comments (in number of spaces)."
  '(+ (* eif-feature-level-comment-indent eif-indent-increment)
      eif-extra-feature-level-comment-indent))

(defmacro eif-check-keyword-indent-m ()
  "Indentation amount for Check keyword (in number of spaces)."
  '(+ (* eif-check-keyword-indent eif-indent-increment)
      eif-extra-check-keyword-indent))

(defmacro eif-rescue-keyword-indent-m ()
  "Indentation amount for Rescue keyword (in number of spaces)."
  '(+ (* eif-rescue-keyword-indent eif-indent-increment)
      eif-extra-rescue-keyword-indent))

(defmacro eif-then-indent-m ()
  "Indentation amount for `then' appearing on a line by itself (in number of spaces)."
  '(+ (* eif-then-indent eif-indent-increment)
      eif-extra-then-indent))

(defmacro eif-continuation-indent-m ()
  "Indentation amount for a statement continuation line (in number of spaces)."
  '(+ (* eif-continuation-indent eif-indent-increment)
      eif-extra-continuation-indent))

(defmacro eif-string-continuation-indent-m ()
  "Indentation amount for a statement continuation line (in number of spaces)."
  '(+ (* eif-string-continuation-indent eif-indent-increment)
      eif-extra-string-continuation-indent))

(defmacro eif-preprocessor-indent-m ()
  "Indentation amount for a preprocessor statement (in number of spaces)."
  '(* eif-preprocessor-indent eif-indent-increment))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;          Keyword Regular Expression Constants.               ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defconst eif-non-id-char-regexp "\\S_" ;; "[^a-z0-9_]"
  "The characters that are not part of identifiers.")

(defun eif-post-anchor (regexp)
  "Anchor given REGEXP with end-word delimiter and `eif-non-id-char-regexp'."
  (concat "\\(" regexp "\\)\\>" eif-non-id-char-regexp))

(defun eif-word-anchor (regexp)
  "Anchor given REGEXP with word delimiters and `eif-non-id-char-regexp'."
  (concat "\\<\\(" regexp "\\)\\>" eif-non-id-char-regexp))

(defun eif-anchor (regexp)
  "Anchor given REGEXP front and back to match line break or non-symbol char."
  (concat "\\(^\\|\\S_\\<\\)\\(" regexp "\\)\\($\\|\\>\\S_\\)"))

;; Note invariant is handled as a special case since it is both a
;; class-level and a from-level keyword
;; Note obsolete is handled as a special case since it is both a
;; class-level and a feature-level keyword
;; Note create, note, and indexing are also handled as special cases
(defconst eif-class-level-keywords
  (concat
   "\\(?:"
   (regexp-opt '("deferred" "expanded" "reference" "separate"))
   "[ \t]+\\)?class"
   "\\|"
   (regexp-opt '("inherit" "insert" "convert" "creation" "feature")))
  "Keywords introducing class-level clauses.
Note that `invariant', `obsolete', `indexing', `note', and `create' are not included here since can
function as more than one type of keyword.")

(defconst eif-class-level-keywords-regexp
  (eif-word-anchor eif-class-level-keywords)
  "Regexp of keywords introducing class level clauses, with some context.
See `eif-class-level-keywords'.")

(defconst eif-inherit-level-keywords
  (regexp-opt '("rename" "redefine" "undefine" "select" "export"))
  "Those keywords which introduce subclauses of the inherit clause.")

(defconst eif-feature-level-keywords
  (regexp-opt '("require" "local" "deferred" "separate" "do" "once" "ensure" "alias" "external" "attribute"))
  "Those keywords which are internal to features (in particular, routines).")

(defconst eif-feature-level-keywords-regexp
  (eif-word-anchor eif-feature-level-keywords)
  "Regexp of keywords internal to features (usually routines).
See `eif-feature-level-keywords'.")

(defconst eif-end-keyword "end" "The `end' keyword.")

(defconst eif-end-on-current-line ".*[ \t]end[ \t]*;?[ \t]*\\(--.*\\)?$"
  "Regular expression to identify lines ending with the `end' keyword.")

(defconst eif-control-flow-keywords
  (regexp-opt '("if" "inspect" "from" "debug"))
  "Keywords which introduce control-flow constructs.")

(defconst eif-control-flow-matching-keywords
  (concat (regexp-opt '("deferred" "do" "once")) "\\|" eif-control-flow-keywords)
  "Keywords that may cause the indentation of an `eif-control-flow-keyword'.
If these occur prior to an `eif-control-flow-keyword' then the
`eif-control-flow-keyword' is indented.  Note that technically, `end'
is part of this list but it is handled separately in the function
\[eif-matching-kw\].")

(defconst eif-control-flow-matching-keywords-regexp
  (eif-word-anchor eif-control-flow-matching-keywords)
  "Regexp of keywords maybe causing indentation of `eif-control-flow-keyword'.
See `eif-control-flow-keywords'.")

(defconst eif-check-keyword "check"
  "The `check' keyword.")

(defconst eif-check-keywords-regexp
  (eif-word-anchor eif-check-keyword)
  "The `check' keyword (with trailing context).")

;; FIXME: Doesn't work if once keyword is followed by a string on next
;; line, but didn't get broken by this attempt at factoring.
(defconst eif-check-matching-keywords-regexp
  eif-control-flow-matching-keywords-regexp
  "Keywords that may cause the indentation of an `eif-check-keyword'.
If these occur prior to an `eif-check-keyword' then the
`eif-check-keyword' is indented.  Note that technically, `end' is part
of this list but it is handled separately in the function
\[eif-matching-kw\].  See also `eif-control-flow-matching-keywords-regexp'.")

;; FIXME: This could be fixed or removed.
(defconst eif-end-keyword-regexp "\\<end\\>"
  "The `end' keyword with context.")

(defconst eif-end-matching-keywords
  (concat (regexp-opt '("attribute" "check" "class" "feature" "rename" "redefine" "undefine"
          "select" "export" "separate" "external" "alias")) "\\|"
          eif-control-flow-matching-keywords)
  "Those keywords whose clause is terminated by an `end' keyword.")

(defconst eif-end-matching-keywords-regexp
  (eif-word-anchor eif-end-matching-keywords)
  "Regexp of keywords whose clause is terminated by an `end' keyword.
See `eif-end-matching-keywords'.")

(defconst eif-rescue-keyword "rescue"  "The `rescue' keyword.")

(defconst eif-obsolete-keyword "obsolete"  "The `obsolete' keyword.")

(defconst eif-indexing-keyword
  (regexp-opt '("note" "indexing"))
  "The `indexing' and `note' keywords.")

(defconst eif-indexing-keyword-regexp
  (eif-post-anchor eif-indexing-keyword)
  "Regexp matching `indexing' and `note' keywords, with trailing context.")

(defconst eif-rescue-keywords-regexp
  (eif-word-anchor eif-rescue-keyword)
  "The `rescue' keyword (with trailing context).")

(defconst eif-rescue-matching-keywords-regexp
  (eif-word-anchor (regexp-opt '("deferred" "do" "once")))
  "Keywords that may cause the indentation of an `eif-rescue-keyword'.
If these occur prior to an `eif-rescue-keyword' then the
`eif-rescue-keyword' is indented.  Note that technically, `end' is
part of this list but it is handled separately in the function
\[eif-matching-kw\].  See also `eif-control-flow-matching-keywords-regexp'.")

(defconst eif-from-level-keywords
  (regexp-opt '("until" "variant" "loop"))
  "Keywords occuring inside of a from clause.")

(defconst eif-from-level-keywords-regexp
  (eif-word-anchor eif-from-level-keywords)
  "Regexp of keywords occuring inside of a from clause.
See `eif-from-level-keywords'.")

(defconst eif-from-keyword  "from" "The keyword `from'.")

(defconst eif-if-or-inspect-level-keywords
  (regexp-opt '("elseif" "else" "when"))
  "Keywords occuring inside of an if or inspect clause.")

(defconst eif-if-or-inspect-level-keywords-regexp
  (eif-word-anchor eif-if-or-inspect-level-keywords)
  "Regexp of keywords occuring inside of an if or inspect clause.
See eif-if-or-inspect-level-keywords.")

(defconst eif-if-or-inspect-keyword-regexp
  (eif-word-anchor (regexp-opt '("if" "inspect")))
  "Regexp matching the `if' or `inspect' keywords.")

(defconst eif-then-keyword ".*[ \t)]then[ \t]*$"
  "The keyword `then' with possible leading text.")

(defconst eif-solitary-then-keyword "then" "The keyword `then'.")

(defconst eif-then-matching-keywords
  (regexp-opt '("if" "elseif" "when") t)
  "Keywords that may alter the indentation of an `eif-then-keyword'.
If one of these occur prior to an `eif-then-keyword' then this sets
the indentation of the `eif-then-keyword'.  Note that technically,
`end' is part of this list but it is handled separately in the
function \[eif-matching-kw\].  See also
`eif-control-flow-matching-keywords-regexp'.")

(defconst eif-invariant-keyword "invariant" "The `invariant' keyword.")

(defconst eif-invariant-matching-keywords
  (regexp-opt '("from" "feature"))
  "Keywords that may cause the indentation of an `eif-invarient-keyword'.
If one of these occurs prior to an `eif-invariant-keyword' then the
`eif-invariant-keyword' is indented.  Note that technically, `end' is
part of this list but it is handled separately in the function
\[eif-matching-kw\].  See also `eif-control-flow-matching-keywords-regexp'.")

(defconst eif-obsolete-matching-keywords
  (regexp-opt '("is" "class") t)
  "Keywords that may cause the indentation of an `eif-obsolete-keyword'.
If one of these occurs prior to an `eif-obsolete-keyword' then the
`eif-obsolete-keyword' is indented.")

(defconst eif-create-keyword
  "create"
  "Eiffel create keyword.  Can be used at class or minor level.")

(defconst eif-create-keyword-regexp
  (eif-post-anchor eif-create-keyword)
  "Regexp matching `create' keyword, with trailing context.")

(defconst eif-indentation-keywords
  (concat (regexp-opt '("note" "indexing" "rescue" "inherit" "insert" "convert" "create" "creation"
          "invariant" "require" "local" "ensure" "obsolete")) "\\|"
          eif-from-level-keywords "\\|"
          eif-if-or-inspect-level-keywords "\\|"
          eif-end-matching-keywords)
  "Keywords that match any eiffel keyword triggering indentation.")

(defconst eif-indentation-keywords-regexp
  (eif-word-anchor eif-indentation-keywords)
  "Regexp of keywords that match any eiffel keyword triggering indentation.
See `eif-indentation-keywords'.")

(defconst eif-once-non-indent-regexp
  "\\s-*once\\(\\s-\\|\n\\)+\""
  "Regexp of Eiffel once keyword in context not affecting indentation.")

(defconst eif-feature-indentation-keywords-regexp
  (eif-word-anchor (regexp-opt '("convert" "creation" "feature")))
  "Keywords which denote the presence of features following them.")

(defconst eif-is-keyword-regexp "\\(.*[ \t)]\\)?is[ \t]*\\(--.*\\)?$"
  "The `is' keyword (with some context).")

(defconst eif-multiline-routine-is-keyword-regexp
  ".*([^)]*)\\([ \t\n]*\\|[ \t\n]*:[][ \t\nA-Za-x0-9_,]*\\)is[ \t]*\\(--.*\\)?$"
  "The `is' keyword (with some context).")

(defconst eif-operator-keywords
  (regexp-opt '("and" "or" "implies"))
  "Eiffel operator keywords.")

(defconst eif-operator-regexp
  (concat "[ \t]*\\([@*/+]\\|-[^-]\\|\\<\\("
          eif-operator-keywords
          "\\)[ \t(]\\)")
  "Eiffel operators - used to identify continuation lines.
See `eif-operator-keywords'.")

(defconst eif-operator-eol-regexp
  (concat ".*\\([@*/+-]\\|\\<\\(" eif-operator-keywords
          "\\)\\|:=\\)[ \t]*\\(--.*\\)?$")
  "Eiffel operators - used to identify continuation lines.")

(defconst eif-all-keywords
  (concat eif-indentation-keywords    "\\|"
          eif-solitary-then-keyword   "\\|"
          eif-create-keyword          "\\|"
          eif-end-keyword)
  "Regexp matching (nearly) any eiffel keyword in a line.
Does not include `is'.")

(defconst eif-all-keywords-regexp
  (concat "\\("
          (eif-word-anchor eif-all-keywords) "\\)")
  "Anchored regexp matching (nearly) any eiffel keyword in a line.
Does not include `is'.  See `eif-all-keywords'.")

(defconst eiffel-comment-start-skip
  "--+|?[ \t]*"
  "Regexp matching the beginning of an Eiffel comment.")

(defconst eif-non-source-line
  (concat "[ \t]*\\(\\(" "--" "\\).*\\)?$")
  "RE matching line with only whitespace and comment or preprocessor keyword.")

(defconst eif-variable-or-const-regexp "[^()\n]*:[^=].*"
  "RE to match a variable or constant declaration.")

;; Factor out some important important regexps for use in
;; eif-{beginning,end}-of-feature.

(defun eiffel-feature-re ()
  "Liberty Eiffel feature declarations"
  (let* ((argument-name "\\(?:[A-Za-z]*[a-z0-9_]+[A-Za-z0-9_]*\\)")
         (feature-name (concat "\\(?:\\(infix\\|prefix\\)\\s-+\".+?\"\\|" argument-name "\\(?:\\s-+alias\\s-+\".+?\"\\)?\\)"))
         (type-name "\\(?:like\\s-+\\sw+\\|[A-Z]\\sw*\\(?:\\[.+?\\]\\)?\\)"))
    (concat
     "\\(?:"
     "\\(?:\\<frozen\\s-\\)?"
     "\\s-*" feature-name "\\s-*,?"
     "\\)+"
     "\\(?:(" ; no \\s-* because it is matched above, if there is no trailing coma
     "\\(?:"
     "\\(?:\\s-*" argument-name "\\s-*,?\\)+?"
     ":" type-name "\\s-*;?"
     "\\)*?"
     ")\\)?" ; no \\s-* because it is matched above, if there is no trailing semi-colon
     "\\(?:\\s-*:\\s-*" type-name "\\)?"
     "\\(?:\\s-*assign\\s-*\\sw+\\)?"
     "\\(?:\\s-*is\\>\\)?")))

(defconst eif-routine-begin-regexp
  ;"\\([a-z][a-zA-Z_0-9]*\\)\\s-*\\(([^)]*)\\)?\\s-*\\(:\\s-*[A-Z][A-Z0-9_]*\\(\\s-*\\[[^\\]]*\\]\\)?\\)?\\s-*\\(assign\\s-*[a-zA-Z0-9_]+\\)?\\s-*\\<is\\>\\s-*\\(--.*\\)?$"
 (eiffel-feature-re)
  "Regexp matching the beginning of an Eiffel routine declaration.")

(message (concat "Liberty Eiffel features: " eif-routine-begin-regexp))

(defconst eif-attribute-regexp
  (concat "[a-z_][^-:\n]*:\\s-*"
          "\\(like\\s-*[a-zA-Z][a-z_0-9]*\\|"
          "\\(\\(expanded\\|reference\\)\\s-*\\)?[A-Z][A-Z_0-9]*"
          "\\(\\s-*\\[[^-\n]*\\]\\)?\\)"
          "\\s-*\\($\\|[;)].*\\|--.*\\)")
  "Regexp matching an Eiffel attribute, parameter or local variable.")

(defconst eif-constant-regexp
  "[a-z_][^-:\n]*:[^-\n]*\\<is\\>\\s-*[^ \t\n]"
  "Regexp matching an Eiffel constant declaration.")

(defconst eif-probably-feature-regexp
  (concat "\\(" eif-routine-begin-regexp
          "\\|" eif-attribute-regexp
          "\\|" eif-constant-regexp "\\)")
  "Regexp probably matching an Eiffel feature.
This will also match local variable and parameter declarations.")

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defvar eif-matching-indent -1
  "Indentation of the keyword found on the last call to \[eif-matching-kw\].
-1 if no match was found.")

(defvar eif-matching-kw-for-end nil)

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;;
;; Font-lock support.
;;
;; Rewritten from scratch by Cyril Adrian <cyril.adrian@gmail.com>
;; Specific to Liberty Eiffel
;;

(defconst eiffel-keywords-feature
  '("agent" "all" "and" "as" "assign" "attribute" "check" "class"
    "convert" "create" "debug" "deferred" "do" "else" "elseif" "end" "ensure"
    "expanded" "export" "external" "feature" "from" "if" "implies"
    "indexing" "inherit" "insert" "inspect" "invariant" "is" "like"
    "local" "loop" "not" "note" "obsolete" "old" "once" "only" "or"
    "redefine" "rename" "require" "rescue" "retry" "select" "separate" "then"
    "undefine" "until" "variant" "when" "xor"))

(defconst eiffel-keywords
  '("agent" "alias" "all" "and" "as" "assign" "attribute" "check" "class"
    "convert" "create" "debug" "deferred" "do" "else" "elseif" "end" "ensure"
    "expanded" "export" "external" "feature" "from" "frozen" "if" "implies"
    "indexing" "infix" "inherit" "insert" "inspect" "invariant" "is" "like"
    "local" "loop" "not" "note" "obsolete" "old" "once" "only" "or" "prefix"
    "redefine" "rename" "require" "rescue" "retry" "select" "separate" "then"
    "undefine" "until" "variant" "when" "xor"))

(defconst eiffel-constants
  '("Current" "False" "Precursor" "Result" "True" "Void"))

(defun eiffel-string-re ()
  "Liberty Eiffel strings"
  (concat "U?\"\\(?:"
          "\\(?:\\(?:[^%\"\n]\\|%[^\n]\\)*?\\)" ; single-line strings
          "\\|"
          "\\(?:\\(?:[^%\"\n]\\|%[^\n]\\)*?%[ \t]*\n\\(?:[ \t]*%\\(?:[^%\"\n]\\|%[^\n]\\)*?%[ \t]*\n\\)*[ \t]*%\\(?:[^%\"\n]\\|%[^\n]\\)*?\\)" ; older multiline strings
          "\\|"
          "\\(?:[[{][ \t]*\n\\(?:.*?\n\\)*?[ \t]*[]}]\"\\)" ; newer multiline strings
          "\\)\""))

(defun eiffel-wordstart-re ()
  "start of words"
  "\\<\\(")

(defun eiffel-wordend-re ()
  "end of words"
  (concat "\\)\\>"))

(defun eiffel-keywords-re ()
  (concat
   (eiffel-wordstart-re)
   (regexp-opt eiffel-keywords)
   (eiffel-wordend-re)))

(defun eiffel-constants-re ()
  (concat
   (eiffel-wordstart-re)
   (regexp-opt eiffel-constants)
   (eiffel-wordend-re)))

(defun eiffel-preprocessor-re ()
  (concat
   (eiffel-wordstart-re)
   (regexp-opt '("c_inline_c" "c_inline_h" "not_yet_implemented" "se_breakpoint" "breakpoint"  "to_pointer"
                 "is_expanded_type" "is_basic_expanded_type"
                 "object_size" "object_id_memory"
                 "se_guru01" "se_guru02" "se_guru03"))
   (eiffel-wordend-re)))

(defvar eiffel-font-lock-defaults
  (append
   `(
     ("--|\\(.*\\)\n"               .    font-lock-comment-face)
     ("--\\(.*\\)\n"                .    font-lock-doc-face)
     (,(eiffel-string-re)           .    font-lock-string-face)
     ("'\\(?:[^'%]\\|%.\\)'"        .    font-lock-string-face)
     ("\\<\\([A-Z][A-Z0-9_]*\\)\\>" .    font-lock-type-face)
     (,(eiffel-keywords-re)            1 font-lock-keyword-face)
     (,(eiffel-constants-re)           1 font-lock-builtin-face)
     (,(eiffel-preprocessor-re)        1 font-lock-preprocessor-face)))
  "Default highlighting expressions for Liberty Eiffel mode")

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;;
;; Compilation support for GNU SmartEiffel.
;;

(defvar eif-compile-dir nil
  "Current directory where Eiffel compilations are taking place.
Possibly used for error location.")

(defvar eif-root-class nil
  "Current Eiffel root class being compiled/debugged.")

(defvar eif-compile-target nil
  "Current Eiffel compilation target.")

(defvar eif-debug-target nil
  "Current Eiffel debug target.")

(defvar eif-root-proc nil
  "Current Eiffel root procedure.")

(defvar eif-run-command nil
  "Current command to run after Eiffel compile.")

(defvar eif-debug-command nil
  "Current debug command to run after Eiffel debug compile.")

(defun eif-compilation-mode-hook ()
  "Hook function to set local value for `compilation-error-screen-columns'.
This should be nil for SmartEiffel compiles, because column positions are
returned as character positions rather than screen columns."
  ;; In Emacs > 20.7 compilation-error-screen-columns is buffer local.
  (or (assq 'compilation-error-screen-columns (buffer-local-variables))
      (make-local-variable 'compilation-error-screen-columns))
  (setq compilation-error-screen-columns nil))

(defun eif-compile ()
  "Compile an Eiffel root class."
  (interactive)
  (eif-compile-prompt)
  (eif-compile-internal))

(defun eif-set-compile-options ()
  "Set Eiffel compiler options."
  (interactive)
  (setq eif-compile-options
        (read-string "Eiffel compiler options: " eif-compile-options)))

;; Taken from Emacs 20.3 subr.el (just in case we're running under Emacs 19).
(defun eif-split-string (string &optional separators)
  "Split STRING into substrings separated by SEPARATORS.
Each match for SEPARATORS is a splitting point.  The substrings
between the splitting points are made into a list which is returned.
If SEPARATORS is absent, it defaults to \"[ \\f\\t\\n\\r\\v]+\".

If there is match for SEPARATORS at the beginning of STRING, we do not
include a null substring for that.  Likewise, if there is a match
at the end of STRING, we do not include a null substring for that."
  (let ((rexp (or separators "[ \f\t\n\r\v]+"))
        (start 0)
        notfirst
        (list nil))
    (while (and (string-match rexp string
                              (if (and notfirst
                                       (= start (match-beginning 0))
                                       (< start (length string)))
                                  (1+ start) start))
                (< (match-beginning 0) (length string)))
      (setq notfirst t)
      (or (eq (match-beginning 0) 0)
          (and (eq (match-beginning 0) (match-end 0))
               (eq (match-beginning 0) start))
          (setq list
                (cons (substring string start (match-beginning 0))
                      list)))
      (setq start (match-end 0)))
    (or (eq start (length string))
        (setq list
              (cons (substring string start)
                    list)))
    (nreverse list)))

(defun eif-run ()
  "Run a compiled Eiffel program."
  (interactive)
  (setq eif-run-command
        (read-string "Command to run: "
                     (or eif-run-command
                         eif-compile-target
                         (file-name-sans-extension
                          (if (or (eq system-type 'windows-nt) (eq system-type 'cygwin))
                              buffer-file-name
                            (file-name-nondirectory (buffer-file-name)))))))
  (eif-run-internal))

(defun eif-debug ()
  "Run the SmartEiffel debugger."
  (interactive)

  (eif-compile-prompt)

  (setq eif-debug-target
        (file-name-sans-extension
         (read-string "Debug target name: "
                      (or eif-debug-target
                          (concat eif-compile-target "_debug")))))

  (let* ((eif-compile-options (concat "-sedb " eif-compile-options))
         (eif-compile-target eif-debug-target)
         (buff (eif-compile-internal))
         (proc (get-buffer-process buff)))

    ;; This works under GNU Emacs, but hangs under at least some
    ;; versions of XEmacs if there is input pending.
    (while (eq (process-status proc) 'run)
      (sit-for 1))

    (if (= (process-exit-status proc) 0)
        (progn
          (setq eif-debug-command
                (read-string "Debugger command to run: "
                             (or eif-debug-command
                                 eif-debug-target
                                 (file-name-sans-extension
                                  (if (eq system-type 'windows-nt)
                                      buffer-file-name
                                    (file-name-nondirectory
                                     (buffer-file-name)))))))
          (let ((eif-run-command eif-debug-command))
            (eif-run-internal))))))

(defun eif-compile-prompt ()
  "Prompt for information required to compile an Eiffel root class."

  ;; Do the save first, since the user might still have their hand on
  ;; the mouse.
  (save-some-buffers (not compilation-ask-about-save) nil)

  (setq eif-compile-dir (file-name-directory (buffer-file-name)))
  (setq eif-root-class
        (file-name-sans-extension
         (read-string "Name of root class: "
                      (or eif-compile-target
                          (file-name-sans-extension
                           (file-name-nondirectory (buffer-file-name)))))))
  (setq eif-compile-target eif-root-class)
  (setq eif-root-proc
        (read-string "Name of root procedure: "
                     eif-root-proc)))

(defun eif-compile-internal ()
  "Compile an Eiffel root class.  Internal version.
Returns the same thing as \\[compilation-start] - the compilation buffer."

  (let ((cmd (concat eif-se-command
                     " compile -flymake_mode "
                            eif-compile-options
                     " -o " eif-compile-target
                     (if (eq system-type 'windows-nt) ".exe")
                     " "    eif-root-class
                     " "    eif-root-proc))
        (buf-name "*Liberty Eiffel Compilation*")
        (compilation-mode-hook (cons 'eif-compilation-mode-hook
                                     compilation-mode-hook)))
    (if (fboundp 'compilation-start) ; Emacs 22 and above
        (compilation-start cmd nil #'(lambda (mode-name) buf-name))
      (compile-internal cmd "No more errors" buf-name))))

(defun eif-run-internal ()
  "Run a compiled Eiffel program.  Internal version."

  (let* ((tmp-buf (current-buffer))
         (words   (eif-split-string eif-run-command))
         (cmd     (expand-file-name (car words))))

    (apply 'make-comint cmd cmd nil (cdr words))
    (switch-to-buffer tmp-buf)
    (switch-to-buffer-other-window (concat "*" cmd "*"))))

;; This has been loosened up to spot parts of messages that contain
;; references to multiple locations.  Thanks to Andreas
;; <nozone@sbox.tu-graz.ac.at>.  Also, the column number is a character
;; count rather than a screen column, so we need to make sure that
;; compilation-error-screen-columns is nil.  Note that in XEmacs this
;; variable doesn't exist, so we end up in the wrong column.  Hey, at
;; least we're on the correct line!
(add-to-list 'compilation-error-regexp-alist
             '("^Line \\([0-9]+\\) column \\([0-9]+\\) in [^ ]+ (\\([^)]+\\.[Ee]\\))" 3 1 2))

(defun eif-find-file (&optional userclass)
  "Find and open an Eiffel file given by a class name"
  (interactive)
  (let* ((cn (or userclass (current-word))))
    (if (string-match "[A-Z][0-9A-Z_]*" cn)
        (let ((classname (substring cn (match-beginning 0) (match-end 0))))
         (message "Searching %s..." classname)
         (let* ((shellres (shell-command-to-string (concat "se find --raw " classname)))
                (filename (substring shellres 0 (string-match "\n" shellres))))
           (find-file filename)
           )))
  (message nil)))

(defun eif-short ()
  "Display the short form of an Eiffel class."
  (interactive)
  (let* ((class (read-string
                 "Class or file: "
                 (if (buffer-file-name)
                     (file-name-nondirectory (buffer-file-name)))))
         (buf (get-buffer-create (concat "*Eiffel - short " class "*"))))

    (shell-command (concat eif-se-command " short " class) buf)
    (with-current-buffer buf
      (let ((font-lock-defaults eiffel-font-lock-defaults))
        (font-lock-fontify-buffer))
      (read-only-mode 1))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;                      Utility Functions.                      ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defun eif-feature-quote ()
  "Put a `' around the current feature name."
  (interactive)
  (save-excursion
    ;; Only try to go back to the beginning of the feature if we're
    ;; not already there.
    (if (/= (point)
            (save-excursion
              (forward-sexp)
              (backward-sexp)
              (point)))
        (backward-sexp))
    (insert "`")
    (forward-sexp)
    (insert "'"))
  (if (looking-at "'")
      (forward-char 1)))

(defun eif-peeking-backwards-at (regexp)
  "Return non-nil is previous character exists and is matched by REGEXP.
The match is actually an unbounded match starting at the previous character."
  (save-excursion
    (save-match-data
      (and (not (bobp))
           (or (backward-char) t)
           (looking-at regexp)))))

(defsubst eif-in-comment-p ()
  "Return t if point is in a comment."
  (interactive)
  (save-excursion
    (nth 4 (parse-partial-sexp
            (save-excursion (beginning-of-line) (point))
            (point)))))

(defun eif-in-comment-or-quoted-string-p ()
  "Return t if point is in a comment or quoted string."
  (or (eif-in-comment-p)
      (eif-in-quoted-string-p)))

(defun eif-not-in-comment-or-quoted-string-p ()
  "Return t if point is not in a comment or quoted string."
  (not (eif-in-comment-or-quoted-string-p)))

(defun eif-near-comment-p ()
  "Return t if point is close enough to a comment for filling purposes."
  (or (eif-in-comment-p)
      (and (or (looking-at comment-start-skip)
               (eif-peeking-backwards-at comment-start-skip))
           (not (eif-in-quoted-string-p)))
      (looking-at (concat "[ \t]*" comment-start-skip))))

(defun eif-re-search-forward (regexp &optional limit noerror)
  "Search forward from point for REGEXP not in comment or string.
`case-fold-search' is set to nil when searching.  For details on other
arguments see \\[re-search-forward]."

  (interactive "sRE search: ")
  (let ((start (point))
        found case-fold-search)
    (while (and (setq found (re-search-forward regexp limit noerror))
                (eif-in-comment-or-quoted-string-p)))
    (if (and found
            (eif-not-in-comment-or-quoted-string-p))
        found
      (if (eq noerror t)
          (goto-char start))
      nil)))

(defun eif-re-search-backward (regexp &optional limit noerror)
  "Search backward from point for REGEXP not in comment or string.
`case-fold-search' is set to nil when searching.  For details on other
arguments see \\[re-search-forward]."
  (interactive "sRE search: ")
  (let ((start (point))
        found case-fold-search)
    (while (and (setq found (re-search-backward regexp limit noerror))
                (eif-in-comment-or-quoted-string-p)))
    (if (and found
            (eif-not-in-comment-or-quoted-string-p))
        found
      (if (eq noerror t)
          (goto-char start))
      nil)))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;                      Indentation Functions.                  ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defun eif-skip-leading-whitespace ()
  "Move to the first non-whitespace character on the current line."
      (end-of-line)
      (let ((line-end (point)))
        (beginning-of-line)
        (skip-syntax-forward "-" line-end)))

(defun eif-calc-indent ()
  "Calculate the indentation of the current line of eiffel code.
This function handles the case where there is a keyword that affects
indentation at the beginning of the current line.  For lines that
don't start with a relevant keyword, the calculation is handed off to
\\[eif-calc-non-keyword-indent]."
  (let ((indent   0)
        kw-match)

    (save-excursion
      (eif-skip-leading-whitespace)

      ;; Look for a keyword on the current line.
      (if (looking-at eif-all-keywords-regexp)

          (cond ((looking-at eif-create-keyword-regexp)
                 ;; Class-level or minor occurence?
                 (if (save-excursion (eif-find-beginning-of-feature))
                     ;; Minor.
                     (setq indent (eif-calc-indent-non-keyword))
                   ;; Class-level.
                   (setq indent (eif-class-level-kw-indent-m))))
                ;; There's possibly a better way of coding this exception.
                ((looking-at eif-once-non-indent-regexp)
                 (setq indent (eif-calc-indent-non-keyword)))
                ((looking-at eif-indexing-keyword-regexp)
                 ;; Class-level or minor occurence?
                 (if (string-match eif-check-keyword (eif-matching-kw eif-check-keywords-regexp))
                     ;; In check.
                     (setq indent (+ eif-matching-indent (eif-check-keyword-indent-m)))
                   (if (save-excursion (eif-find-beginning-of-feature))
                       ;; Minor. (BUG: "note" can also be at the END of the class!!!)
                       (setq indent (eif-calc-indent-non-keyword))
                     ;; Class-level.
                     (setq indent (eif-class-level-kw-indent-m)))))
                ((looking-at eif-class-level-keywords-regexp)
                 ;; File level keywords (indent defaults to 0)
                 (setq indent (eif-class-level-kw-indent-m)))
                ((looking-at eif-inherit-level-keywords)
                 ;; Inherit level keywords (indent defaults to
                 ;; 2*eif-indent-increment)
                 (setq indent (eif-inherit-level-kw-indent-m)))
                ((looking-at eif-feature-level-keywords-regexp)
                 ;; Feature level keywords (indent defaults to
                 ;; (eif-feature-level-indent-m) + eif-indent-increment)
                 (setq indent (eif-feature-level-kw-indent-m)))
                ((looking-at eif-end-keyword)
                 ;; End keyword (indent to level of matching keyword)
                 (if (string-match "end"
                                   (eif-matching-kw
                                    eif-end-matching-keywords-regexp))
                     ;; Then
                     (if (= eif-matching-indent
                            (eif-feature-level-kw-indent-m))
                         ;; Then
                         (setq indent (eif-class-level-kw-indent-m))
                       ;; Else
                       (setq indent
                             (- eif-matching-indent eif-indent-increment)))
                   ;; Else
                   (setq indent eif-matching-indent))
                 ;; FIXME: This is broken!!!
                 (if (<= indent (eif-feature-level-indent-m))
                     (save-excursion
                       (end-of-line)
                       (while (and (< (point) (point-max))
                                   (or (forward-char 1) t)
                                   (looking-at eif-non-source-line))
                         (end-of-line))
                       (if (not (looking-at eif-non-source-line))
                           (setq indent (eif-inherit-level-kw-indent-m))
                         (setq indent (eif-class-level-kw-indent-m))))))
                ((looking-at eif-control-flow-keywords)
                 ;; Control flow keywords
                 ;;  Indent to same level as a preceding "end" or
                 ;;  if no preceding "end" is found, indent to the level
                 ;;  of the preceding "do" plus the value of
                 ;;  eif-indent-increment
                 (setq kw-match
                       (eif-matching-kw
                        eif-control-flow-matching-keywords-regexp))
                 (cond ((string-match "end" kw-match)
                        (setq indent eif-matching-indent))
                       (t
                        (setq indent
                              (+ eif-matching-indent eif-indent-increment)))))
                ((looking-at eif-check-keywords-regexp)
                 ;; Check keyword
                 ;;  Indent to level of preceding "end"+eif-indent-increment or
                 ;;  if no preceding "end" is found, indent to the level of
                 ;;  the preceding eif-check-matching-keywords-regexp plus the
                 ;;  value (eif-indent-increment + eif-check-keyword-indent).

                 (setq kw-match (eif-matching-kw
                                 eif-check-matching-keywords-regexp))
                 (cond ((string-match "end" kw-match)
                        (setq indent (+ eif-matching-indent
                                        (eif-check-keyword-indent-m))))
                       (t
                        (setq indent
                              (+ eif-matching-indent
                                 (+ eif-indent-increment
                                    (eif-check-keyword-indent-m)))))))
                ((looking-at eif-rescue-keywords-regexp)
                 ;; Rescue keyword
                 ;;  Indent to level of preceding "end"+eif-indent-increment or
                 ;;  if no preceding "end" is found, indent to the level of
                 ;;  the preceding eif-rescue-matching-keywords-regexp plus the
                 ;;  value (eif-indent-increment + eif-rescue-keyword-indent).
                 (setq kw-match (eif-matching-kw
                                 eif-rescue-matching-keywords-regexp))
                 (cond ((string-match "end" kw-match)
                        (setq indent (+ eif-matching-indent
                                        (eif-rescue-keyword-indent-m))))
                       (t
                        (setq indent eif-matching-indent))))
                ((looking-at eif-from-level-keywords-regexp)
                 ;; From level keywords (indent to level of matching "From")
                 (if (string-match "end" (eif-matching-kw eif-from-keyword))
                     ;; Closest matching KW is `end'.
                     (setq indent (- eif-matching-indent eif-indent-increment))
                   ;; Closest matching KW is one of `eif-from-keyword'.
                   (setq indent eif-matching-indent)))
                ((looking-at eif-if-or-inspect-level-keywords-regexp)
                 ;; If level keywords (indent to level of matching
                 ;; "If" or "Inspect")
                 (if (string-match "end"
                                   (eif-matching-kw
                                    eif-if-or-inspect-keyword-regexp))
                     ;; Closest matching KW is `end'.
                     (setq indent (- eif-matching-indent eif-indent-increment))
                   ;; Closest matching KW is one of `eif-if-or-inspect-keyword-regexp'.
                   (setq indent eif-matching-indent)))
                ((looking-at eif-solitary-then-keyword)
                 ;; Handles case where "then" appears on a line by itself
                 (if (eif-matching-kw eif-then-matching-keywords t)
                     ;; (Indented to level of the matching if, elseif or when)
                     (setq indent (+ eif-matching-indent (eif-then-indent-m)))
                   (if (save-excursion (eif-find-beginning-of-feature))
                       ;; (Feature-level "then")
                       (setq indent (eif-feature-level-kw-indent-m))
                     (message "Non-matching 'then'")
                     (setq indent (eif-calc-indent-non-keyword)))))
                ((looking-at eif-invariant-keyword)
                 ;; Invariant keyword
                 ;;   (Indented to level of the matching from or feature)
                 (if (string-match "from"
                                   (eif-matching-kw eif-invariant-matchi…