Tools.h++ Manual

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21
RWSequenceable
RWSequenceable
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RWCollection
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RWCollectable
Synopsis #include <rw/seqcltn.h>
typedef RWSequenceable SequenceableCollection; // Smalltalk
typedef
Description Class RWSequenceable is an abstract base class for collections that can be
accessed via an index. It inherits class RWCollection as a public base class
and adds a few extra virtual functions. This documentation only describes
these extra functions.
Public member functions RWCollectable* append(RWCollectable*) = 0;
Adds the item to the end of the collection and returns it. Returns nil if the
insertion was unsuccessful.
virtual RWCollectable*& at(size_t i);
virtual const RWCollectable* at(size_t i) const;
Allows access to the i 'th element of the collection. The first variant can be
used as an lvalue, the second cannot. The index i must be between zero and
the number of items in the collection less one, or an exception of type
RWBoundsErr will be thrown.
virtual RWCollectable* first() const = 0;
Returns the first item in the collection.
virtual size_t index(const RWCollectable* c)
const = 0;
Returns the index number of the first item that "matches" the item pointed to
by c . If there is no such item, returns RW_NPOS . For most collections, an item
"matches" the target if either isEqual() or compareTo() find equivalence,
whichever is appropriate for the actual collection type.