--- /dev/null
+## Copyright (C) 2009-2012 S�ren Hauberg
+##
+## This file is part of Octave.
+##
+## Octave 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 3 of the License, or (at
+## your option) any later version.
+##
+## Octave 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 Octave; see the file COPYING. If not, see
+## <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {} gen_doc_cache (@var{out_file}, @var{directory})
+## Generate documentation caches for all functions in a given directory.
+##
+## A documentation cache is generated for all functions in @var{directory}.
+## The
+## resulting cache is saved in the file @var{out_file}.
+## The cache is used to speed up @code{lookfor}.
+##
+## If no directory is given (or it is the empty matrix), a cache for builtin
+## operators, etc. is generated.
+##
+## @seealso{lookfor, path}
+## @end deftypefn
+
+function gen_doc_cache (out_file = "doc-cache", directory = [])
+
+ ## Check input
+ if (!ischar (out_file))
+ print_usage ();
+ endif
+
+ ## Generate cache
+ if (isempty (directory))
+ cache = gen_builtin_cache ();
+ elseif (ischar (directory))
+ cache = gen_doc_cache_in_dir (directory);
+ else
+ error ("gen_doc_cache: second input argument must be a string");
+ endif
+
+ ## Save cache
+ if (! isempty (cache))
+ save ("-text", out_file, "cache");
+ endif
+endfunction
+
+function [text, first_sentence, status] = handle_function (f, text, format)
+ first_sentence = "";
+ ## Skip functions that start with __ as these shouldn't be searched by lookfor
+ if (length (f) > 2 && all (f (1:2) == "_"))
+ status = 1;
+ return;
+ endif
+
+ ## Take action depending on help text format
+ switch (lower (format))
+ case "plain text"
+ status = 0;
+ case "texinfo"
+ [text, status] = __makeinfo__ (text, "plain text");
+ case "html"
+ [text, status] = strip_html_tags (text);
+ otherwise
+ status = 1;
+ endswitch
+
+ ## Did we get the help text?
+ if (status != 0 || isempty (text))
+ warning ("gen_doc_cache: unusable help text found in file '%s'", f);
+ return;
+ endif
+
+ ## Get first sentence of help text
+ first_sentence = get_first_help_sentence (f);
+endfunction
+
+function cache = create_cache (list)
+ cache = {};
+
+ ## For each function:
+ for n = 1:length (list)
+ f = list {n};
+
+ ## Get help text
+ [text, format] = get_help_text (f);
+
+ [text, first_sentence, status] = handle_function (f, text, format);
+
+ ## Did we get the help text?
+ if (status != 0)
+ continue;
+ endif
+
+ ## Store the help text
+ cache (1, end+1) = f;
+ cache (2, end) = text;
+ cache (3, end) = first_sentence;
+ endfor
+endfunction
+
+function cache = gen_doc_cache_in_dir (directory)
+ ## If 'directory' is not in the current path, add it so we search it
+ dir_in_path = false;
+ p = path ();
+ idx = find (p == pathsep ());
+ prev_idx = 1;
+ for n = 1:length (idx)
+ f = p (prev_idx:idx (n)-1);
+ if (strcmp (f, directory))
+ dir_in_path = true;
+ break;
+ endif
+ prev_idx = idx (n) + 1;
+ endfor
+
+ if (!dir_in_path)
+ addpath (directory);
+ endif
+
+ ## Get list of functions in directory and create cache
+ list = __list_functions__ (directory);
+ cache = create_cache (list);
+
+ if (!dir_in_path)
+ rmpath (directory);
+ endif
+endfunction
+
+function cache = gen_builtin_cache ()
+ operators = __operators__ ();
+ keywords = __keywords__ ();
+ builtins = __builtins__ ();
+ list = {operators{:}, keywords{:}, builtins{:}};
+
+ cache = create_cache (list);
+endfunction
+
+
+%% No true tests desirable for this function.
+%% Test input validation
+%!error gen_doc_cache (1)
+