This page last updated 19 April 2001.

This meeting is arranged by Martin Smith

The Power of Parsing

Dr Brian Warburton

Introduction

The idea for this work arose out of a desire to write simple Microsoft-type Windows Applications using standard C language without recourse to more sophisticated systems such as C++, Visual Basic or Visual C++. The aim of the present stage of work is to write a simple C compiler using the Parser Olias.

The parser Olias can also be used to translate one style of assembly language into another, e.g. Cware Assembler into Borland or Microsoft. Olias works in a similar way to the Unix Parser GREP. However GREP only recognizes string patterns and on its own is not able to make string substitutions.

The C compiler will operate in several stages:
1) Generation of suitable Assembler
2) Compilation of the Assembler to give Object code.
3) The latter will conform to any required standard e.g. Borland or Microsoft.
4) Method of Operation:
Olias works by reading a series of parsing commands from a Command Script file. These commands are then carried out making major editorial changes to the original C file. When these changes are complete a finished Assemby file is produced.

The command line syntax is:
Olias foo.c command.oli
Where foo.c is the source c language file and command.oli is the Command Script file.

Steps so far Completed

Recognition of the C type initialization statements for Integer, long and unsigned.
Double, Char and String to follow.
Recognition of C type function calls.
Provision is made to repeat commands where necessary.

Advantages of the System

The main advantage of the system is its flexibility, e.g. Any known style of Assembly language may be achieved in translation, e.g. Borland, Microsoft, Cware. "Mangled" function or variable names, again may chosen to order by the selection of a suitable Command script file. Olias is a master, universal programme and does not need to be revised or recompiled.
Another advantage of this type of programming is that the driving programme is relatively short 14KB and so executes rapidly.

For further information, contact:
Dr Brian Warburton
BeeWarb EnterPrises
37A Oatlands Avenue
Weybridge
Surrey KT13 9SS, UK
E-mail:BrWarburto@AOL.com

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