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From: sfk@hplb.hpl.hp.com (Steve Knight)
Subject: Re: Extending Syntax in Pop
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Date: Tue, 14 Mar 1995 13:03:02 GMT
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David Whitten (whitten@netcom.com) wrote:
> I talked to someone who told me that Pop has syntax extension capabilities.
> I am interested in adding a language (MUMPS) to the languages suported in 
> a POPLOG system.  From what I know of Pop, Prolog, and ML, it looks like
> most of the system level support I would expect to successfully implement
> a MUMPS system is already provided in a typical Poplog implementation.

Yes, I think it would be quite feasible.  My experience in writing
compilers inside Poplog has been that the hardest problem is designing
the namespace support mechanism -- because Poplog does not provide
any means of creating a new empty namespace (i.e. you cannot create
new top-level sections.) 

To find out more you really need to read REF VMCODE, REF KEYS, and
REF SUBSYSTEM.  (If you don't have a copy then mail julianc@integ.co.uk)  
The main problem in learning how to write compilers in Poplog is the 
lack of simple examples.

Steve
