1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
|
namespace Eva {
public class Var : Object, Term {
public string name {get; construct;}
public Var(string name0) {
assert(name0.get_char() == '_' || name0.get_char().isupper());
Object(name: name0);
}
public string to_string() {
return name;
}
internal static string alias(string key, Gee.Map<string, string> aliases) {
if(!(key in aliases))
return key;
else
return alias(aliases[key], aliases);
}
protected bool do_match(Term o, Gee.Map<string, Term> vars, Gee.Map<string, string> aliases) {
if(name == "_") {
return true;
}
string key = alias(name, aliases);
if(o is Var) {
Var v = o as Var;
if(v.name == "_") {
return true;
}
string vkey = alias(v.name, aliases);
if(key == vkey)
return true;
if(key in vars && vkey in vars)
return vars[key].do_match(vars[vkey], vars, aliases);
else if(!(vkey in vars)) {
aliases[vkey] = key;
return true;
}
else /* !(key in vars) */ {
aliases[key] = vkey;
return true;
}
}
else {
if(key in vars) {
return vars[key].do_match(o, vars, aliases);
}
else {
vars[key] = o;
return true;
}
}
}
public void encode(Erl.Buffer buffer) {
assert_not_reached();
}
}
}
|