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Date:Mon Jul 21 18:32:35 1994 
Subject:Re: Reading POP-11 expressions without tears. 
From:johnw (John Williams) 
Volume-ID:940722.03 

>Ever wanted to read a POP-11 expression and NOT compile it? The following
>little hackeroo does it:

There is already an autoloadable library (LIB * EXPRREAD) in Poplog
that does this. -exprread- is defined as:

	define global exprread = proglist_read_by(%pop11_comp_expr%) enddefine;

and -proglist_read_by- is a built-in system procedure documented in REF PROGLIST
as:

 proglist_read_by(read_p) -> list                             [procedure]
         Given any  procedure read_p  which  reads items  from  proglist,
         executes read_p and returns a separate list of the items it read
         (which are removed from proglist).
 
         pop_syntax_only is locally set  true while read_p is  executing.
         Thus if read_p is a procedure that compiles (e.g.) Pop-11  code,
         the only effect  will be to  return the list  of items it  read,
         without actually planting any Poplog VM code.

John.