Subject: Re: emphasixe on this weeks work

From: Zheng Gengbing <[email-masked]>
Date: Wed, 24 Apr 1996 16:11:49 +0800 (EAT)

On Tue, 23 Apr 1996, Guansong Zhang wrote:

> And again I hope pku provide information on hpfcc, I don't get response about
> the following from pku yet.
> 
> Is it possible for unparse to treat the .dep before and after hpfcc as same? If
> not, why?
> 

	I remember we have dicussed this issue before . As I think if your
unparser are designed according to  the specification of AST , it will be
ok in most of case . That's mean perhaps in those cases that we changed some 
AST specification while you are using the old defintion , you unparse will
fail .

	There is some subtle issues you must notice . In some cases ,
we will change the dep dramatically . But the change is still according 
to the AST specification . I remember I have given this example :

	f(x)= x*3

this is a statement function statement . this means it is a small function
declaration , not an assignment . In the first parse , yacc cannot tell them
apart , and you will find there is no STMT_FUNC_STMT bfnd in yacc .
So we must differentiate this kind of bfnd from ASSIGN statement bfnd 
according to the context .
	2.  yacc did not do very well to discrimnate 
SUB_STRING from ARRAY_REF . We will check it out and reconstruct the tree .
	3.  when yacc fail to discrimnate a func call from  a array type
such as  a(1,2) , it's our task to check it out and convert the ARRAY_REF 
tree to FUNC_CALL tree.
        4.  ...

	From the points above , you can find though we changed dep , we are
still based on the AST specification . So if your unparse can unparse all
the bfnd specified in AST , it certainly can parse the dep processed by
hpfcc.

	So , the most important thing is that our work are all based on
a same AST specification .If that is the case , we certainly need not
worry about the binding our work .
	I think in many times we both sides modified yacc actions to change the 
AST in one_side without consider the other side . It is not strange that we 
will meet trouble when we merged our work .

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