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1
4 package kawa.standard;
5 import kawa.lang.*;
6 import gnu.lists.*;
7 import gnu.expr.*;
8 import gnu.math.*;
9 import gnu.bytecode.*;
10
11 public class define_unit extends Syntax
12 {
13 public static final define_unit define_unit = new define_unit(false);
14 static { define_unit.setName("define-unit"); }
15 public static final define_unit define_base_unit = new define_unit(true);
16 static { define_base_unit.setName("define-base-unit"); }
17
18
19 boolean base;
20
21 public define_unit (boolean base)
22 {
23 this.base = base;
24 }
25
26 public boolean scanForDefinitions (Pair st, java.util.Vector  forms,
27 ScopeExp defs, Translator tr)
28 {
29 if (st.cdr instanceof Pair)
30 {
31 Pair p = (Pair) st.cdr;
32 Object q = p.car;
33 if (q instanceof String )
34 {
35 String name = (String ) q;
36 String sym = (name + "$unit").intern();
37 Declaration decl = defs.getDefine(sym, 'w', tr);
38 tr.push(decl);
39 Translator.setLine(decl, p);
40 decl.setFlag(Declaration.IS_CONSTANT);
41 if (defs instanceof ModuleExp)
42 decl.setCanRead(true);
43 Unit unit = null;
44 if (base && p.cdr == LList.Empty)
45 unit = BaseUnit.make(name, (String ) null);
46 else if (p.cdr instanceof Pair)
47 {
48 Object v = ((Pair) p.cdr).car;
49 if (base && v instanceof FString)
50 unit = BaseUnit.make(name, v.toString());
51 else if (! base && v instanceof Quantity)
52 unit = Unit.make(name, (Quantity) v);
53 }
54 if (unit != null)
55 decl.noteValue(new QuoteExp(unit));
56 p = Translator.makePair(p, decl, p.cdr);
57 st = Translator.makePair(st, this, p);
58 forms.addElement (st);
59 return true;
60 }
61 }
62 tr.error('e', "missing name in define-unit");
63 return false;
64 }
65
66 public Expression rewriteForm (Pair form, Translator tr)
67 {
68 Object obj = form.cdr;
69 Expression value = null;
70 Pair p1;
71
72 if (! (obj instanceof Pair)
73 || ! ((p1 = (Pair) obj).car instanceof Declaration))
74 return tr.syntaxError ("invalid syntax for "+getName());
75 Declaration decl = (Declaration) p1.car;
76 String name = decl.getName();
77 String unit = name.substring(0, name.length() - 5).intern(); ClassType unitType = ClassType.make("gnu.math.Unit");
79 decl.setType(unitType);
80 if ((value = decl.getValue()) instanceof QuoteExp
81 && ((QuoteExp) value).getValue() instanceof Unit)
82 ;
83 else if (base)
84 {
85 String dimension = null;
86 if (p1.cdr != LList.Empty)
87 {
88 dimension = ((Pair) p1.cdr).car.toString();
89 }
90 BaseUnit bunit = BaseUnit.make(unit, dimension);
91 value = new QuoteExp(bunit);
92 }
93 else
94 {
95 if (! (p1.cdr instanceof Pair))
96 return tr.syntaxError("missing value for define-unit");
97 Pair p2 = (Pair) p1.cdr;
98 value = tr.rewrite (p2.car);
99 Object quantity;
100 if (value instanceof QuoteExp
101 && (quantity = ((QuoteExp) value).getValue()) instanceof Quantity)
102 {
103 value = new QuoteExp(Unit.make(unit, (Quantity) quantity));
104 }
105 else
106 {
107 Expression[] args = new Expression[2];
108 args[0] = new QuoteExp(unit);
109 args[1] = value;
110 value = gnu.kawa.reflect.Invoke.makeInvokeStatic(unitType, "make",
111 args);
112 }
113 }
114 SetExp sexp = new SetExp(decl, value);
115 sexp.setDefining (true);
116 decl.noteValue(value);
117 return sexp;
118 }
119 }
120 |
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