template.h

// Compiler implementation of the D programming language
// Copyright (c) 1999-2011 by Digital Mars
// All Rights Reserved
// written by Walter Bright
// http://www.digitalmars.com
// License for redistribution is by either the Artistic License
// in artistic.txt, or the GNU General Public License in gnu.txt.
// See the included readme.txt for details.

#ifndef DMD_TEMPLATE_H
#define DMD_TEMPLATE_H

#ifdef __DMC__
#pragma once
#endif /* __DMC__ */

#include "root.h"
#include "arraytypes.h"
#include "dsymbol.h"


struct OutBuffer;
struct Identifier;
struct TemplateInstance;
struct TemplateParameter;
struct TemplateTypeParameter;
struct TemplateThisParameter;
struct TemplateValueParameter;
struct TemplateAliasParameter;
struct TemplateTupleParameter;
struct Type;
struct TypeTypeof;
struct Scope;
struct Expression;
struct AliasDeclaration;
struct FuncDeclaration;
struct HdrGenState;
enum MATCH;

struct Tuple : Object
{
    Objects objects;

    int dyncast() { return DYNCAST_TUPLE; } // kludge for template.isType()
};


struct TemplateDeclaration : ScopeDsymbol
{
    TemplateParameters *parameters;     // array of TemplateParameter's

    TemplateParameters *origParameters; // originals for Ddoc
    Expression *constraint;
    TemplateInstances instances;        // array of TemplateInstance's

    TemplateDeclaration *overnext;      // next overloaded TemplateDeclaration
    TemplateDeclaration *overroot;      // first in overnext list

    int semanticRun;                    // 1 semantic() run

    Dsymbol *onemember;         // if !=NULL then one member of this template

    int literal;                // this template declaration is a literal
    int ismixin;                // template declaration is only to be used as a mixin

    struct Previous
    {   Previous *prev;
        Scope *sc;
        Objects *dedargs;
    };
    Previous *previous;         // threaded list of previous instantiation attempts on stack

    TemplateDeclaration(Loc loc, Identifier *id, TemplateParameters *parameters,
        Expression *constraint, Dsymbols *decldefs, int ismixin);
    Dsymbol *syntaxCopy(Dsymbol *);
    void semantic(Scope *sc);
    int overloadInsert(Dsymbol *s);
    void toCBuffer(OutBuffer *buf, HdrGenState *hgs);
    bool hasStaticCtorOrDtor();
    const char *kind();
    char *toChars();

    void emitComment(Scope *sc);
    void toJsonBuffer(OutBuffer *buf);
//    void toDocBuffer(OutBuffer *buf);

    MATCH matchWithInstance(TemplateInstance *ti, Objects *atypes, Expressions *fargs, int flag);
    MATCH leastAsSpecialized(TemplateDeclaration *td2, Expressions *fargs);

    MATCH deduceFunctionTemplateMatch(Scope *sc, Loc loc, Objects *targsi, Expression *ethis, Expressions *fargs, Objects *dedargs);
    FuncDeclaration *deduceFunctionTemplate(Scope *sc, Loc loc, Objects *targsi, Expression *ethis, Expressions *fargs, int flags = 0);
    void declareParameter(Scope *sc, TemplateParameter *tp, Object *o);
    FuncDeclaration *doHeaderInstantiation(Scope *sc, Objects *tdargs, Expressions *fargs);

    TemplateDeclaration *isTemplateDeclaration() { return this; }

    TemplateTupleParameter *isVariadic();
    int isOverloadable();

    void makeParamNamesVisibleInConstraint(Scope *paramscope, Expressions *fargs);
};

struct TemplateParameter
{
    /* For type-parameter:
     *  template Foo(ident)             // specType is set to NULL
     *  template Foo(ident : specType)
     * For value-parameter:
     *  template Foo(valType ident)     // specValue is set to NULL
     *  template Foo(valType ident : specValue)
     * For alias-parameter:
     *  template Foo(alias ident)
     * For this-parameter:
     *  template Foo(this ident)
     */

    Loc loc;
    Identifier *ident;

    Declaration *sparam;

    TemplateParameter(Loc loc, Identifier *ident);

    virtual TemplateTypeParameter  *isTemplateTypeParameter();
    virtual TemplateValueParameter *isTemplateValueParameter();
    virtual TemplateAliasParameter *isTemplateAliasParameter();
#if DMDV2
    virtual TemplateThisParameter *isTemplateThisParameter();
#endif
    virtual TemplateTupleParameter *isTemplateTupleParameter();

    virtual TemplateParameter *syntaxCopy() = 0;
    virtual void declareParameter(Scope *sc) = 0;
    virtual void semantic(Scope *) = 0;
    virtual void print(Object *oarg, Object *oded) = 0;
    virtual void toCBuffer(OutBuffer *buf, HdrGenState *hgs) = 0;
    virtual Object *specialization() = 0;
    virtual Object *defaultArg(Loc loc, Scope *sc) = 0;

    /* If TemplateParameter's match as far as overloading goes.
     */
    virtual int overloadMatch(TemplateParameter *) = 0;

    /* Match actual argument against parameter.
     */
    virtual MATCH matchArg(Scope *sc, Objects *tiargs, size_t i, TemplateParameters *parameters, Objects *dedtypes, Declaration **psparam) = 0;

    /* Create dummy argument based on parameter.
     */
    virtual void *dummyArg() = 0;
};

struct TemplateTypeParameter : TemplateParameter
{
    /* Syntax:
     *  ident : specType = defaultType
     */
    Type *specType;     // type parameter: if !=NULL, this is the type specialization
    Type *defaultType;

    static Type *tdummy;

    TemplateTypeParameter(Loc loc, Identifier *ident, Type *specType, Type *defaultType);

    TemplateTypeParameter *isTemplateTypeParameter();
    TemplateParameter *syntaxCopy();
    void declareParameter(Scope *sc);
    void semantic(Scope *);
    void print(Object *oarg, Object *oded);
    void toCBuffer(OutBuffer *buf, HdrGenState *hgs);
    Object *specialization();
    Object *defaultArg(Loc loc, Scope *sc);
    int overloadMatch(TemplateParameter *);
    MATCH matchArg(Scope *sc, Objects *tiargs, size_t i, TemplateParameters *parameters, Objects *dedtypes, Declaration **psparam);
    void *dummyArg();
};

#if DMDV2
struct TemplateThisParameter : TemplateTypeParameter
{
    /* Syntax:
     *  this ident : specType = defaultType
     */
    Type *specType;     // type parameter: if !=NULL, this is the type specialization
    Type *defaultType;

    TemplateThisParameter(Loc loc, Identifier *ident, Type *specType, Type *defaultType);

    TemplateThisParameter *isTemplateThisParameter();
    TemplateParameter *syntaxCopy();
    void toCBuffer(OutBuffer *buf, HdrGenState *hgs);
};
#endif

struct TemplateValueParameter : TemplateParameter
{
    /* Syntax:
     *  valType ident : specValue = defaultValue
     */

    Type *valType;
    Expression *specValue;
    Expression *defaultValue;

    static AA *edummies;

    TemplateValueParameter(Loc loc, Identifier *ident, Type *valType, Expression *specValue, Expression *defaultValue);

    TemplateValueParameter *isTemplateValueParameter();
    TemplateParameter *syntaxCopy();
    void declareParameter(Scope *sc);
    void semantic(Scope *);
    void print(Object *oarg, Object *oded);
    void toCBuffer(OutBuffer *buf, HdrGenState *hgs);
    Object *specialization();
    Object *defaultArg(Loc loc, Scope *sc);
    int overloadMatch(TemplateParameter *);
    MATCH matchArg(Scope *sc, Objects *tiargs, size_t i, TemplateParameters *parameters, Objects *dedtypes, Declaration **psparam);
    void *dummyArg();
};

struct TemplateAliasParameter : TemplateParameter
{
    /* Syntax:
     *  specType ident : specAlias = defaultAlias
     */

    Type *specType;
    Object *specAlias;
    Object *defaultAlias;

    static Dsymbol *sdummy;

    TemplateAliasParameter(Loc loc, Identifier *ident, Type *specType, Object *specAlias, Object *defaultAlias);

    TemplateAliasParameter *isTemplateAliasParameter();
    TemplateParameter *syntaxCopy();
    void declareParameter(Scope *sc);
    void semantic(Scope *);
    void print(Object *oarg, Object *oded);
    void toCBuffer(OutBuffer *buf, HdrGenState *hgs);
    Object *specialization();
    Object *defaultArg(Loc loc, Scope *sc);
    int overloadMatch(TemplateParameter *);
    MATCH matchArg(Scope *sc, Objects *tiargs, size_t i, TemplateParameters *parameters, Objects *dedtypes, Declaration **psparam);
    void *dummyArg();
};

struct TemplateTupleParameter : TemplateParameter
{
    /* Syntax:
     *  ident ...
     */

    TemplateTupleParameter(Loc loc, Identifier *ident);

    TemplateTupleParameter *isTemplateTupleParameter();
    TemplateParameter *syntaxCopy();
    void declareParameter(Scope *sc);
    void semantic(Scope *);
    void print(Object *oarg, Object *oded);
    void toCBuffer(OutBuffer *buf, HdrGenState *hgs);
    Object *specialization();
    Object *defaultArg(Loc loc, Scope *sc);
    int overloadMatch(TemplateParameter *);
    MATCH matchArg(Scope *sc, Objects *tiargs, size_t i, TemplateParameters *parameters, Objects *dedtypes, Declaration **psparam);
    void *dummyArg();
};

struct TemplateInstance : ScopeDsymbol
{
    /* Given:
     *  foo!(args) =>
     *      name = foo
     *      tiargs = args
     */
    Identifier *name;
    //Identifiers idents;
    Objects *tiargs;            // Array of Types/Expressions of template
                                // instance arguments [int*, char, 10*10]

    Objects tdtypes;            // Array of Types/Expressions corresponding
                                // to TemplateDeclaration.parameters
                                // [int, char, 100]

    TemplateDeclaration *tempdecl;      // referenced by foo.bar.abc
    TemplateInstance *inst;             // refer to existing instance
    TemplateInstance *tinst;            // enclosing template instance
    ScopeDsymbol *argsym;               // argument symbol table
    AliasDeclaration *aliasdecl;        // !=NULL if instance is an alias for its
                                        // sole member
    WithScopeSymbol *withsym;           // if a member of a with statement
    int semanticRun;    // has semantic() been done?
    int semantictiargsdone;     // has semanticTiargs() been done?
    int nest;           // for recursion detection
    int havetempdecl;   // 1 if used second constructor
    Dsymbol *isnested;  // if referencing local symbols, this is the context
    int errors;         // 1 if compiled with errors
    int speculative;    // 1 if only instantiated with errors gagged
#ifdef IN_GCC
    /* On some targets, it is necessary to know whether a symbol
       will be emitted in the output or not before the symbol
       is used.  This can be different from getModule(). */
    Module * objFileModule;
#endif

    TemplateInstance(Loc loc, Identifier *temp_id);
    TemplateInstance(Loc loc, TemplateDeclaration *tempdecl, Objects *tiargs);
    static Objects *arraySyntaxCopy(Objects *objs);
    Dsymbol *syntaxCopy(Dsymbol *);
    void semantic(Scope *sc, Expressions *fargs);
    void semantic(Scope *sc);
    void semantic2(Scope *sc);
    void semantic3(Scope *sc);
    void inlineScan();
    void toCBuffer(OutBuffer *buf, HdrGenState *hgs);
    Dsymbol *toAlias();                 // resolve real symbol
    const char *kind();
    int oneMember(Dsymbol **ps, Identifier *ident);
    int needsTypeInference(Scope *sc);
    char *toChars();
    char *mangle();
    void printInstantiationTrace();

    void toObjFile(int multiobj);                       // compile to .obj file

    // Internal
    static void semanticTiargs(Loc loc, Scope *sc, Objects *tiargs, int flags);
    void semanticTiargs(Scope *sc);
    TemplateDeclaration *findTemplateDeclaration(Scope *sc);
    TemplateDeclaration *findBestMatch(Scope *sc, Expressions *fargs);
    void declareParameters(Scope *sc);
    int hasNestedArgs(Objects *tiargs);
    Identifier *genIdent(Objects *args);

    TemplateInstance *isTemplateInstance() { return this; }
    AliasDeclaration *isAliasDeclaration();
};

struct TemplateMixin : TemplateInstance
{
    Identifiers *idents;
    Type *tqual;

    TemplateMixin(Loc loc, Identifier *ident, Type *tqual, Identifiers *idents, Objects *tiargs);
    Dsymbol *syntaxCopy(Dsymbol *s);
    void semantic(Scope *sc);
    void semantic2(Scope *sc);
    void semantic3(Scope *sc);
    void inlineScan();
    const char *kind();
    int oneMember(Dsymbol **ps, Identifier *ident);
    int hasPointers();
    char *toChars();
    void toCBuffer(OutBuffer *buf, HdrGenState *hgs);

    void toObjFile(int multiobj);                       // compile to .obj file

    TemplateMixin *isTemplateMixin() { return this; }
};

Expression *isExpression(Object *o);
Dsymbol *isDsymbol(Object *o);
Type *isType(Object *o);
Tuple *isTuple(Object *o);
int arrayObjectIsError(Objects *args);
int isError(Object *o);
Type *getType(Object *o);
Dsymbol *getDsymbol(Object *o);

void ObjectToCBuffer(OutBuffer *buf, HdrGenState *hgs, Object *oarg);
Object *objectSyntaxCopy(Object *o);

#endif /* DMD_TEMPLATE_H */