source: translator/Designators/Processor.cc @ 2c2242c

#include <vector>
#include <algorithm>

#include "Processor.h"
#include "SynTree/Declaration.h"

namespace Designators {
    Matcher::Matcher( const std::list< DeclarationWithType * > &decls ) {
        int cnt = 0;
        for ( std::list< DeclarationWithType * >::const_iterator i = decls.begin();
             i != decls.end(); i++, cnt++ ) {
            std::string newName = (*i)->get_name();
            if ( table.find( newName ) == table.end() ) {
                table.insert( std::pair<std::string, int>(newName, cnt) );
                order.push_back( newName );
                declarations.push_back( *i );
                alternatives.push_back( 0 );
            }
        }
    }

    template< class InputIterator >
    bool Matcher::add(InputIterator begin, InputIterator end, ResolvExpr::Alternative &alt ) {
        while ( begin != end ) {
            if ( table.find( *begin ) != table.end() )
                alternatives[ table[ *begin ] ] = new ResolvExpr::Alternative(alt);
            else
                return false;
            begin++;
        }
        return true;
    }

    template< class InputIterator, class OutputIterator >
    bool Matcher::slice(InputIterator begin, InputIterator end, OutputIterator out ) {
        while ( begin != end )
            if ( table.find( *begin ) != table.end() )
                *out++ = declarations [ table[ *begin++ ] ];
            else
                return false; // throw 0;
        return true;
    }

    template< class OutputIterator >
    bool Matcher::get_reorderedCall( OutputIterator out ) {
        // fill call with defaults, if need be
        for (Matcher::iterator o = begin(); o != end(); o++ )
            if ( alternatives[ table[ *o ] ] == 0 )
                return false;
            else
                out++ = *alternatives[table[ *o ]];
        return true;
    }

    bool fixDesignations( ResolvExpr::AlternativeFinder &finder, Expression *designation ) {
        // Distribute `designation' over alternatives contained in `finder'
        if ( ! designation) return false;
        else
            for ( ResolvExpr::AlternativeFinder::iterator alt = finder.begin(); alt != finder.end(); alt++ )
                alt->expr->set_argName( designation );
        return true;
    }

    template < class OutputIterator >
    bool extractNames( Expression *expr, OutputIterator out, Matcher matcher ) {
        Expression *designator = expr->get_argName();
        if ( designator == 0 ) return false;

        if ( NameExpr *ndes = dynamic_cast<NameExpr *>(designator) )
            out++ = ndes->get_name();
        else if ( TupleExpr *tdes = dynamic_cast<TupleExpr *>(designator) ) {
            std::cerr << "Tuple designation" << std::endl;
//      ObjectDecl *decl = extractTupleV(matcher, tdes); // xxx
            // transform?
            for ( std::list< Expression * >::iterator n = tdes->get_exprs().begin();
                 n != tdes->get_exprs().end(); n++ ) {

                if ( NameExpr *name = dynamic_cast<NameExpr *>(*n) )
                    out++ = name->get_name();
                else
                    // flatten nested Tuples
                    throw SemanticError( "Invalid tuple designation." );
            }
        }
        return true;
    }

    std::string extractName( Expression *expr ) /* throw NoNameExtraction */ {
        if ( NameExpr *name = dynamic_cast< NameExpr *>(expr) )
            return name->get_name();
        else /* if () */
            throw 0;
    }

    DeclarationWithType *gensym( DeclarationWithType *, std::string prefix ) {
        return 0;
    }

    ObjectDecl *extractTupleV( Matcher matcher, TupleExpr *nmTuple ) {
        // extract a subtuple of the function `fun' argument list, corresponding to the tuple of names requested by
        // `nmTuple'.
        std::list< Expression * > &exprs = nmTuple->get_exprs();
        std::cerr << "In extractTupleV, the tuple has " << exprs.size() << " components." << std::endl;
        std::list< std::string > names;
        std::transform( exprs.begin(), exprs.end(), back_inserter(names), extractName );
        std::list< DeclarationWithType * > decls;
        matcher.slice( names.begin(), names.end(), back_inserter(decls) );
        //std::for_each( decls.begin(), decls.end(), gensym );
        std::cerr << "Returning declaration with " << decls.size() << " components." << std::endl;

        return 0;//new ObjectDecl()
    }

    void check_alternative( FunctionType *fun, ResolvExpr::AltList &args ) {
        using namespace ResolvExpr;

        Matcher matcher( fun->get_parameters() );
        for ( AltList::iterator a = args.begin(); a != args.end(); a++ ) {
            std::list< std::string > actNames;
            if ( ! extractNames( a->expr, back_inserter(actNames), matcher ) ) {
                return; // not a designated call, leave alternative alone
            } else {
                // see if there's a match
                matcher.add( actNames.begin(), actNames.end(), *a );
            }
        }
        //AltList newArgs;
        args.clear();
        matcher.get_reorderedCall( back_inserter(args) );

        return;
    }
#if 0
    void pruneAlternatives( Expression *expr, ResolvExpr::AlternativeFinder &finder ) {
        if ( expr->get_argName() != 0 ) {
            // Looking at designated expression
            using namespace ResolvExpr;
            AltList &alternatives = finder.get_alternatives();
            std::cerr << "Now printing alternatives: " << std::endl;
            for ( AltList::iterator a = alternatives.begin(); a != alternatives.end(); a++ )
                a->expr->print( std::cerr );
            //std::cerr << "Looking for constructions of length no more than: " << tdes->get_exprs().size() << "." << std::endl;
        }
        return;
    }
#endif // 0
} // namespaces Designators