Re: Emacs contributions, C and Lisp

[Eli Zaretskii]

> Date: Wed, 07 Jan 2015 14:25:01 -0500
> From: Richard Stallman <address@hidden>
> CC: address@hidden, address@hidden, address@hidden,
>       address@hidden
> 
> It certainly can be done with less.  For instance, if the code says
> 
>   foo.x + bar.y
> 
> or
> 
>   foo.x - bar.y
> 
> it makes no difference for completion what that operator is.

In an object-oriented language that supports operator overloading, the
+ or - can do anything, and accept only specific data types under
certain constraints.  For example, if foo.x is of a certain data type,
the candidates for the right-hand operand might be restricted to a
small subset of what a + or a - can generally support.  If you
complete to a large list of candidates here disregarding the
constraints, you'd leave a lot of users unhappy.

How do you know that kind of information without parsing the whole
program yourself?