1		% (c) 2009-2013 Lehrstuhl fuer Softwaretechnik und Programmiersprachen,
2		% Heinrich Heine Universitaet Duesseldorf
3		% This software is licenced under EPL 1.0 (http://www.eclipse.org/org/documents/epl-v10.html)
4
5		:- module(units_alias, [
6		unit_alias/2,
7		init_user_defined_alias/0
8		]).
9
10		:- use_module(probsrc(pragmas)).
11		:- use_module(probsrc(error_manager)).
12
13		:- use_module(unit_parser).
14
15		:- use_module(probsrc(module_information)).
16		:- module_info(group,plugin_units).
17		:- module_info(description,'Units Plugin: Short aliases for commonly used units.').
18
19		init_user_defined_alias :-
20		findall(alias(AliasName,Definition),
21		global_pragma(unit_alias,[AliasName|Definition]),
22		List),
23		init_user_defined_alias2(List).
24
25		init_user_defined_alias2([]).
26		init_user_defined_alias2([alias(AliasName,Definition)|T]) :-
27		unit_args_to_list(Definition,List),
28	?	((\+ unit_alias(AliasName,List2), List2 \= List) -> add_error(incorrect_unit_definition, 'Unit Alias used twice: ', AliasName) ; true),
29		assert(unit_alias(AliasName,List)),
30		init_user_defined_alias2(T).
31
32		:- dynamic unit_alias/2.
33
34		% lengths
35		unit_alias(mm, [[-3,m,1]]).
36		unit_alias(cm, [[-2,m,1]]).
37		unit_alias(dm, [[-1,m,1]]).
38		unit_alias(m, [[0,m,1]]).
39		unit_alias(km, [[3,m,1]]).
40
41		% railway-specific units
42		unit_alias(hm, [[0,hm,1]]). % half-meter
43
44		% volume
45		unit_alias(l, [[-3,m,3]]).
46
47		% time
48		unit_alias(s, [[0,s,1]]).
49		unit_alias(mins, [[0,mins,1]]).
50		unit_alias(h, [[0,h,1]]).
51		unit_alias(d, [[0,d,1]]).
52
53		% speed
54		unit_alias(mps, [[0,m,1],[0,s,-1]]).
55		unit_alias(kmh, [[3,m,1],[0,h,-1]]).
56
57		% temperature
58		unit_alias(degC, [[0,degC,1]]).
59		unit_alias('K', [[0,'K',1]]).