Add LookupTable class for finding classes and members by name.

Add LookupTable class for finding classes and members by name.

The new class becomes a superclass of CoreTypes, which now gets its
functionality from that class, but also exposes commonly used built-in
members as fields.

This replaces a couple of ad-hoc linear searches spread throughout
the code.

The canonical names are not a convenient interface for transformers, so
the idea is that they can use LookupTable to address their own runtime
libraries.

To avoid name clashes and still have a somewhat convenient interface,
getters and setters are prefixed by 'get:' and 'set:' in the lookup
table (and only in the lookup table), and top-level members can be
accessed using '::' as the class name. This is the same convention
used by the VM, although it is currently not required to be the same.

BUG=

[asgerf, 2017-02-23 16:32:47]

Description was changed from

==========
Add LookupTable class for finding classes and members by name.

The new class becomes a superclass of CoreTypes, which now gets its
functionality from that class, but also exposes commonly used built-in
members as fields.

This replaces a couple of ad-hoc linear searches spread throughout
the code.

The canonical names are not a convenient interface for transformers, so
the idea is that they can use LookupTable to address their own runtime
libraries.

To avoid name clashes and still have a somewhat convenient interface,
getters and setters are prefixed by 'get:' and 'set:' in the lookup
table (and only in the lookup table).

BUG=
==========

to

==========
Add LookupTable class for finding classes and members by name.

The new class becomes a superclass of CoreTypes, which now gets its
functionality from that class, but also exposes commonly used built-in
members as fields.

This replaces a couple of ad-hoc linear searches spread throughout
the code.

The canonical names are not a convenient interface for transformers, so
the idea is that they can use LookupTable to address their own runtime
libraries.

To avoid name clashes and still have a somewhat convenient interface,
getters and setters are prefixed by 'get:' and 'set:' in the lookup
table (and only in the lookup table), and top-level members can be
accessed using '::' as the class name.  This is the same convention
used by the VM.

BUG=
==========

[asgerf, 2017-02-23 16:33:12]

Description was changed from

==========
Add LookupTable class for finding classes and members by name.

The new class becomes a superclass of CoreTypes, which now gets its
functionality from that class, but also exposes commonly used built-in
members as fields.

This replaces a couple of ad-hoc linear searches spread throughout
the code.

The canonical names are not a convenient interface for transformers, so
the idea is that they can use LookupTable to address their own runtime
libraries.

To avoid name clashes and still have a somewhat convenient interface,
getters and setters are prefixed by 'get:' and 'set:' in the lookup
table (and only in the lookup table), and top-level members can be
accessed using '::' as the class name.  This is the same convention
used by the VM.

BUG=
==========

to

==========
Add LookupTable class for finding classes and members by name.

The new class becomes a superclass of CoreTypes, which now gets its
functionality from that class, but also exposes commonly used built-in
members as fields.

This replaces a couple of ad-hoc linear searches spread throughout
the code.

The canonical names are not a convenient interface for transformers, so
the idea is that they can use LookupTable to address their own runtime
libraries.

To avoid name clashes and still have a somewhat convenient interface,
getters and setters are prefixed by 'get:' and 'set:' in the lookup
table (and only in the lookup table), and top-level members can be
accessed using '::' as the class name. This is the same convention
used by the VM, although it is currently not required to be the same.

BUG=
==========