--- /dev/null
+## Copyright (C) 2009 VZLU Prague, a.s., Czech Republic
+##
+## This program 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.
+##
+## This program 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
+## this program; if not, see <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn{Function File} {d =} subsasgn (d, s, val)
+## Overloaded subsasgn for dictionaries.
+## @end deftypefn
+
+## Author: Jaroslav Hajek <highegg@gmail.com>
+
+function d = subsasgn (d, s, val)
+ if (isempty (s))
+ error ("dict: missing index");
+ endif
+
+ switch (s(1).type)
+ case "()"
+ ind = s(1).subs;
+ if (numel (ind) == 1)
+ ind = ind{1};
+ else
+ error ("dict: needs exactly one index");
+ endif
+ if (ischar (ind))
+ ## Scalar assignment case. Search whether the key is present.
+ i = lookup (d.keys, ind, "m");
+ if (i)
+ ## The key is present; handle the rest of chain if needed,
+ ## then assign.
+ if (numel (s) > 1)
+ val = subsasgn (d.values{i}, s(2:end), val);
+ endif
+ d.values{i} = val;
+ else
+ ## The key is missing; handle the rest of chain if needed.
+ if (numel (s) > 1)
+ val = subsasgn ([], s(2:end), val);
+ endif
+ ## Look up the proper place to insert the new key.
+ i = lookup (d.keys, ind);
+ d.keys = [d.keys(1:i,1); {ind}; d.keys(i+1:end,1)];
+ ## Insert value.
+ d.values = [d.values(1:i,1); {val}; d.values(i+1:end,1)];
+ endif
+ elseif (iscellstr (ind))
+ ## Multiple assignment case. Perform checks.
+ if (numel (s) > 1)
+ error ("chained subscripts not allowed for multiple fields");
+ endif
+ if (isnull (val))
+ ## Deleting elements.
+ i = lookup (d.keys, ind, "m");
+ i = i(i != 0);
+ d.keys(i) = [];
+ d.values(i) = [];
+ elseif (iscell (val))
+ if (numel (val) == 1)
+ val = repmat (val, size (ind));
+ elseif (numel (ind) != numel (val))
+ error ("numbers of elements of index and rhs must match");
+ endif
+ ## Choose from two paths.
+ if (numel (ind) < numel (d.keys))
+ ## Scarce assignment. There's a good chance that all keys will be present.
+ i = lookup (d.keys, ind, "m");
+ mask = i != 0;
+ if (all (mask))
+ d.values(i) = val;
+ else
+ d.values(i(mask)) = val(mask);
+ mask = !mask;
+ [d.keys, i] = sort ([d.keys; ind(mask)(:)]);
+ d.values = [d.values; val(mask)(:)](i);
+ endif
+ else
+ ## Mass assignment. Probably most of the keys are new ones, so simply
+ ## melt all together.
+ [d.keys, i] = unique ([d.keys; ind(:)]);
+ d.values = [d.values; val(:)](i);
+ endif
+ else
+ error ("expected cell rhs for cell index");
+ endif
+ else
+ error ("invalid index");
+ endif
+ otherwise
+ error ("invalid subscript type for assignment");
+ endswitch
+endfunction
+