# Interpreter Based on Denotational Semantics

Date: Mon, 4 Nov 91 17:15:11 +0100
Organization: Universitaet des Saarlandes
D-W-6600 Saarbruecken, Germany
An
O ' s m a l l   I n t e r p r e t e r

is now available via anonymous ftp. The object-oriented programming language
O'small can be found in [Hen91c]. A description of the prototypical
interpreter is contained in the technical report [Hen91g]. A dvi-file of
this technical report is also available via anonymous ftp.

HOW TO GET IT
-------------

To obtain the interpreter by internet ftp, connect to host ftp.cs.uni-sb.de
directory  /pub. Go to directory /pub/osmall ("cd osmall").  Then put ftp
in binary mode ("binary") and "get" the relevant files in that directory.

ftp.cs.uni-sb.de	 134.96.7.254	anonymous   Your name	/pub/osmall

The directory /pub/osmall contains a file named README that contains this
information and the following compressed tar file:

osmall.0.1.tar.Z       : a directory called parser and a directory
called interpreter

***************************************************************************
NOTE: Ftp should be put into binary mode before transferring the compressed
tar file.
***************************************************************************

Here is a sample dialog:

ftp
ftp> open ftp.cs.uni-sb.de
Name: anonymous
ftp> binary
ftp> cd osmall
ftp> get osmall.0.1.tar.Z
ftp> close
ftp> quit

REFERENCES
----------

@TECHREPORT{Hen91g,
author = "A. V. Hense",
title = "An O'small Interpreter Based on Denotational Semantics",
institution = unisb,
number = "A 07/91",
month = nov,
year = 1991}

@InProceedings{Hen91c,
title={Wrapper Semantics of an Object-Oriented Programming Language
with State},
author={A. V. Hense},
pages={548--568},
crossref={TACS91},
abstract={The semantics of class inheritance has first been given in
operational form (method-lookup-semantics).  While this semantics is
well suited for implementing object-oriented programming languages, it
may conceal the true nature of inheritance.  The development of
denotational semantics for object-oriented languages has culminated in
object creation as fixed point operation.  Cook gave a semantics on
this basis, using so called {\em wrappers}.  This semantics abstracts
>from the internal state of objects ({\em instance variables\/}).
\par
In this paper we show how wrapper semantics can be extended to an
object-oriented programming language {\em with state\/} while keeping
the structure of the original definitions.  For this purpose we define
a direct denotational semantics of a small example language.  The
insertion of state into class definitions can be done before or after
the related fixed point operation.  The choice of the alternative
considerably influences the semantic domains and clauses.}
}

@Proceedings{TACS91,
title={Theoretical Aspects of Computer Software},
booktitle={Theoretical Aspects of Computer Software},
editor={T. Ito and A. R. Meyer},
series={Lecture Notes in Computer Science},
volume=526,
year=1991,
month=sep,
publisher={Springer-Verlag}
}

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*************************************
Andreas V. Hense
Fachbereich 14 - Informatik
Universitaet des Saarlandes
D - 6600 Saarbruecken 11
Telefon:	0681/302-2464
Telefax:        0681/302-4421
e-mail:		hense@cs.uni-sb.de
*************************************