typesem.c revision 1.1.1.1 
1
2/* Compiler implementation of the D programming language
3 * Copyright (C) 1999-2019 by The D Language Foundation, All Rights Reserved
4 * written by Walter Bright
5 * http://www.digitalmars.com
6 * Distributed under the Boost Software License, Version 1.0.
7 * http://www.boost.org/LICENSE_1_0.txt
8 */
9
10#include "mtype.h"
11#include "expression.h"
12#include "template.h"
13
14Expression *typeToExpression(Type *t);
15Expression *typeToExpressionHelper(TypeQualified *t, Expression *e, size_t i = 0);
16
17class TypeToExpressionVisitor : public Visitor
18{
19public:
20    Expression *result;
21    Type *itype;
22
23    TypeToExpressionVisitor(Type *itype)
24    {
25        this->result = NULL;
26        this->itype = itype;
27    }
28
29    void visit(Type *)
30    {
31        result = NULL;
32    }
33
34    void visit(TypeSArray *t)
35    {
36        Expression *e = typeToExpression(t->next);
37        if (e)
38            e = new ArrayExp(t->dim->loc, e, t->dim);
39        result = e;
40    }
41
42    void visit(TypeAArray *t)
43    {
44        Expression *e = typeToExpression(t->next);
45        if (e)
46        {
47            Expression *ei = typeToExpression(t->index);
48            if (ei)
49            {
50                result = new ArrayExp(t->loc, e, ei);
51                return;
52            }
53        }
54        result = NULL;
55    }
56
57    void visit(TypeIdentifier *t)
58    {
59        result = typeToExpressionHelper(t, new IdentifierExp(t->loc, t->ident));
60    }
61
62    void visit(TypeInstance *t)
63    {
64        result = typeToExpressionHelper(t, new ScopeExp(t->loc, t->tempinst));
65    }
66};
67
68/* We've mistakenly parsed this as a type.
69 * Redo it as an Expression.
70 * NULL if cannot.
71 */
72Expression *typeToExpression(Type *t)
73{
74    TypeToExpressionVisitor v = TypeToExpressionVisitor(t);
75    t->accept(&v);
76    return v.result;
77}
78
79/* Helper function for `typeToExpression`. Contains common code
80 * for TypeQualified derived classes.
81 */
82Expression *typeToExpressionHelper(TypeQualified *t, Expression *e, size_t i)
83{
84    //printf("toExpressionHelper(e = %s %s)\n", Token::toChars(e->op), e->toChars());
85    for (; i < t->idents.dim; i++)
86    {
87        RootObject *id = t->idents[i];
88        //printf("\t[%d] e: '%s', id: '%s'\n", i, e->toChars(), id->toChars());
89
90        switch (id->dyncast())
91        {
92            case DYNCAST_IDENTIFIER:
93            {
94                // ... '. ident'
95                e = new DotIdExp(e->loc, e, (Identifier *)id);
96                break;
97            }
98            case DYNCAST_DSYMBOL:
99            {
100                // ... '. name!(tiargs)'
101                TemplateInstance *ti = ((Dsymbol *)id)->isTemplateInstance();
102                assert(ti);
103                e = new DotTemplateInstanceExp(e->loc, e, ti->name, ti->tiargs);
104                break;
105            }
106            case DYNCAST_TYPE:          // Bugzilla 1215
107            {
108                // ... '[type]'
109                e = new ArrayExp(t->loc, e, new TypeExp(t->loc, (Type *)id));
110                break;
111            }
112            case DYNCAST_EXPRESSION:    // Bugzilla 1215
113            {
114                // ... '[expr]'
115                e = new ArrayExp(t->loc, e, (Expression *)id);
116                break;
117            }
118            default:
119                assert(0);
120        }
121    }
122    return e;
123}
124