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1 package polyglot.ext.jl.ast;
2
3 import polyglot.ast.*;
4
5 import polyglot.util.*;
6 import polyglot.visit.*;
7 import polyglot.types.*;
8 import java.util.*;
9
10
15 public class Cast_c extends Expr_c implements Cast
16 {
17 protected TypeNode castType;
18 protected Expr expr;
19
20 public Cast_c(Position pos, TypeNode castType, Expr expr) {
21 super(pos);
22 this.castType = castType;
23 this.expr = expr;
24 }
25
26
27 public Precedence precedence() {
28 return Precedence.CAST;
29 }
30
31
32 public TypeNode castType() {
33 return this.castType;
34 }
35
36
37 public Cast castType(TypeNode castType) {
38 Cast_c n = (Cast_c) copy();
39 n.castType = castType;
40 return n;
41 }
42
43
44 public Expr expr() {
45 return this.expr;
46 }
47
48
49 public Cast expr(Expr expr) {
50 Cast_c n = (Cast_c) copy();
51 n.expr = expr;
52 return n;
53 }
54
55
56 protected Cast_c reconstruct(TypeNode castType, Expr expr) {
57 if (castType != this.castType || expr != this.expr) {
58 Cast_c n = (Cast_c) copy();
59 n.castType = castType;
60 n.expr = expr;
61 return n;
62 }
63
64 return this;
65 }
66
67
68 public Node visitChildren(NodeVisitor v) {
69 TypeNode castType = (TypeNode) visitChild(this.castType, v);
70 Expr expr = (Expr) visitChild(this.expr, v);
71 return reconstruct(castType, expr);
72 }
73
74
75 public Node typeCheck(TypeChecker tc) throws SemanticException
76 {
77 TypeSystem ts = tc.typeSystem();
78
79 if (! ts.isCastValid(expr.type(), castType.type())) {
80 throw new SemanticException("Cannot cast the expression of type \""
81 + expr.type() + "\" to type \""
82 + castType.type() + "\".",
83 position());
84 }
85
86 return type(castType.type());
87 }
88
89 public Type childExpectedType(Expr child, AscriptionVisitor av) {
90 TypeSystem ts = av.typeSystem();
91
92 if (child == expr) {
93 if (castType.type().isReference()) {
94 return ts.Object();
95 }
96 else if (castType.type().isNumeric()) {
97 return ts.Double();
98 }
99 else if (castType.type().isBoolean()) {
100 return ts.Boolean();
101 }
102 }
103
104 return child.type();
105 }
106
107 public String  toString() {
108 return "(" + castType + ") " + expr;
109 }
110
111
112 public void prettyPrint(CodeWriter w, PrettyPrinter tr)
113 {
114 w.begin(0);
115 w.write("(");
116 print(castType, w, tr);
117 w.write(")");
118 w.allowBreak(2, " ");
119 printSubExpr(expr, w, tr);
120 w.end();
121 }
122
123 public Term entry() {
124 return expr.entry();
125 }
126
127 public List acceptCFG(CFGBuilder v, List succs) {
128 v.visitCFG(expr, this);
129 return succs;
130 }
131
132 public List throwTypes(TypeSystem ts) {
133 if (expr.type().isReference()) {
134 return Collections.singletonList(ts.ClassCastException());
135 }
136
137 return Collections.EMPTY_LIST;
138 }
139
140 public boolean isConstant() {
141 return expr.isConstant() && castType.type().isPrimitive();
142 }
143
144 public Object constantValue() {
145 Object v = expr.constantValue();
146
147 if (v == null) {
148 return null;
149 }
150
151 if (v instanceof Boolean ) {
152 if (castType.type().isBoolean()) return v;
153 }
154
155 if (v instanceof String ) {
156 TypeSystem ts = castType.type().typeSystem();
157 if (castType.type().equals(ts.String())) return v;
158 }
159
160 if (v instanceof Double ) {
161 double vv = ((Double ) v).doubleValue();
162
163 if (castType.type().isDouble()) return new Double ((double) vv);
164 if (castType.type().isFloat()) return new Float ((float) vv);
165 if (castType.type().isLong()) return new Long ((long) vv);
166 if (castType.type().isInt()) return new Integer ((int) vv);
167 if (castType.type().isChar()) return new Character ((char) vv);
168 if (castType.type().isShort()) return new Short ((short) vv);
169 if (castType.type().isByte()) return new Byte ((byte) vv);
170 }
171
172 if (v instanceof Float ) {
173 float vv = ((Float ) v).floatValue();
174
175 if (castType.type().isDouble()) return new Double ((double) vv);
176 if (castType.type().isFloat()) return new Float ((float) vv);
177 if (castType.type().isLong()) return new Long ((long) vv);
178 if (castType.type().isInt()) return new Integer ((int) vv);
179 if (castType.type().isChar()) return new Character ((char) vv);
180 if (castType.type().isShort()) return new Short ((short) vv);
181 if (castType.type().isByte()) return new Byte ((byte) vv);
182 }
183
184 if (v instanceof Number ) {
185 long vv = ((Number ) v).longValue();
186
187 if (castType.type().isDouble()) return new Double ((double) vv);
188 if (castType.type().isFloat()) return new Float ((float) vv);
189 if (castType.type().isLong()) return new Long ((long) vv);
190 if (castType.type().isInt()) return new Integer ((int) vv);
191 if (castType.type().isChar()) return new Character ((char) vv);
192 if (castType.type().isShort()) return new Short ((short) vv);
193 if (castType.type().isByte()) return new Byte ((byte) vv);
194 }
195
196 if (v instanceof Character ) {
197 char vv = ((Character ) v).charValue();
198
199 if (castType.type().isDouble()) return new Double ((double) vv);
200 if (castType.type().isFloat()) return new Float ((float) vv);
201 if (castType.type().isLong()) return new Long ((long) vv);
202 if (castType.type().isInt()) return new Integer ((int) vv);
203 if (castType.type().isChar()) return new Character ((char) vv);
204 if (castType.type().isShort()) return new Short ((short) vv);
205 if (castType.type().isByte()) return new Byte ((byte) vv);
206 }
207
208 return null;
210 }
211 }
212 |
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