source: src/examples/iterator.h @ 09a9a8b

#ifndef ITERATOR_H
#define ITERATOR_H

#include "iostream.h"

// An iterator can be used to traverse a data structure.
context iterator( type iterator_type, type elt_type ) {
    // point to the next element
//    iterator_type ?++( iterator_type * );
    iterator_type ++?( iterator_type * );
    iterator_type --?( iterator_type * );

    // can be tested for equality with other iterators
    int ?==?( iterator_type, iterator_type );
    int ?!=?( iterator_type, iterator_type );

    // dereference to get the pointed-at element
    lvalue elt_type *?( iterator_type );
};

context iterator_for ( type iterator_type, type collection_type, type elt_type | iterator( iterator_type, elt_type ) ) {
//    [ iterator_type begin, iterator_type end ] get_iterators( collection_type );
    iterator_type begin( collection_type );
    iterator_type end( collection_type );
};

forall( type iterator_type, type elt_type | iterator( iterator_type, elt_type ) )
void for_each( iterator_type begin, iterator_type end, void (*func)( elt_type ) );

// writes the range [begin, end) to the given stream
forall( type elt_type | writeable( elt_type ),
        type iterator_type | iterator( iterator_type, elt_type ),
        dtype os_type | ostream( os_type ) )
void write_all( iterator_type begin, iterator_type end, os_type *os );

forall( type elt_type | writeable( elt_type ),
        type iterator_type | iterator( iterator_type, elt_type ),
        dtype os_type | ostream( os_type ) )
void write_reverse( iterator_type begin, iterator_type end, os_type *os );

#endif // ITERATOR_H