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digitalmars.D.learn - DMD Symbol Reference Analysis Pass

reply "Per =?UTF-8?B?Tm9yZGzDtnci?= <per.nordlow gmail.com> writes:
Does DMD currently do any analysis of references to a symbol in a 
given scope? If not where could this information be extracted (in 
which visitor/callback) and in what structure should it, if so, 
be stored?

Reason: After having read about Rust's data-flow (and in turn 
escape) analysis I'm very curious about how difficult it would be 
to add more clever type inference, of for example symbol 
mutability, based on this analysis.

I'm asking again because of the work recently done in DIP-25, 
that may be related to this problem.
May 20 2015
parent reply "Per =?UTF-8?B?Tm9yZGzDtnci?= <per.nordlow gmail.com> writes:
On Wednesday, 20 May 2015 at 08:52:23 UTC, Per Nordlöw wrote:

 Does DMD currently do any analysis of references to a symbol in 
 a given scope? If not where could this information be extracted 
 (in which visitor/callback) and in what structure should it, if 
 so, be stored?


I'm guessing

     Scope::insert(Dsymbol*s)
     {
         if (VarDeclaration *vd = s->isVarDeclaration())
         {
             // ..


is of interest. Is there another member function called everytime 
a Dsymbol is referenced?

I'm guessing MODFlags plays a role here aswell.
May 20 2015
parent reply "Per =?UTF-8?B?Tm9yZGzDtnci?= <per.nordlow gmail.com> writes:
On Wednesday, 20 May 2015 at 09:27:06 UTC, Per Nordlöw wrote:

Two cases come to my mind:

A: Non-Templated Function: must be  safe (or perhaps  trusted) 
pure and parameter must qualified as const (or in).
B: Templated Function: Usage of parameter in body must be 
non-mutating; meaning no lhs of assignment op (=, +=, ...), and 
calls to functions that take parameter as argument must be 
transitively fulfill A and B.
May 20 2015
parent reply "Per =?UTF-8?B?Tm9yZGzDtnci?= <per.nordlow gmail.com> writes:
On Wednesday, 20 May 2015 at 09:41:09 UTC, Per Nordlöw wrote:

 On Wednesday, 20 May 2015 at 09:27:06 UTC, Per Nordlöw wrote:


Ping!?
May 21 2015
parent "John Colvin" <john.loughran.colvin gmail.com> writes:
On Thursday, 21 May 2015 at 11:52:34 UTC, Per Nordlöw wrote:

 On Wednesday, 20 May 2015 at 09:41:09 UTC, Per Nordlöw wrote:

 On Wednesday, 20 May 2015 at 09:27:06 UTC, Per Nordlöw wrote:


 Ping!?


I think you'd be more likely to get responses to this sort of 
question in the main group, not D.learn, it's a bit beyond 
"Learning D".
May 21 2015