So there's no way to macroexpand the module in the module scope itself? 
I don't mind evaluating the module, but how do I then dump out the 
macroexpanded version of it?

If there's a way to "clear" global scope then it would also be possible to 
eval the module, expand in global scope, clean global scope, rinse/repeat 
on next module.
Is there a way to do that instead?


On Monday, March 21, 2016 at 11:55:47 AM UTC-7, Tim Holy wrote:
>
> Interesting. julia's `macroexpand` function doesn't seem to work for 
> expressions inside a module: 
>
> julia> macroexpand( :(module M @time(1+1) end)) 
> :(module M 
>     eval(x) = begin  # none, line 1: 
>             top(Core).eval(M,x) 
>         end 
>     eval(m,x) = begin  # none, line 1: 
>             top(Core).eval(m,x) 
>         end # none, line 1: 
>     @time 1 + 1 
>     end) 
>
> which is the same thing you get back if you omit the `macroexpand`. 
>
> Try commenting out the module declaration and see if you like it better. 
>
> Best, 
> --Tim 
>
> On Monday, March 21, 2016 11:15:56 AM [email protected] <javascript:> 
> wrote: 
> > The MacroExpandJL package seems promising, but maybe I'm not able to get 
> it 
> > to work. After updating syntax to match julia 0.4, 
> > MacroExpandJL.macroexpand_jl(STDOUT, :(module M function f(x) 1+@m(2) 
> end 
> > end)) 
> > module M 
> > begin  # line 1: 
> >     function f(x) # line 1: 
> >         1 + @m 2 
> >     end 
> > endend 
> > 
> > Notice how the @m 2 is still there. Also, why is everything wrapped in 
> an 
> > extra do block inside the module? Is this a printing issue, because that 
> > expression doesn't have one. 
> > 
> > How would I go about evaluating a module and it's macros, macro 
> expanding 
> > the whole thing, and then dumping it out? @eval seems like, name wise, 
> it 
> > should do this but it doesn't. 
> > Do you first eval() the module, then @eval the module? That didn't work 
> for 
> > me either. 
> > 
> > Predefining a macro and then trying to evaluate: 
> > > macro m(x) 1 end 
> > > @eval(:(module M function f(x) @m 2 end end)) 
> > : 
> > :(module M 
> > 
> >     eval(x) = begin  # none, line 1: 
> >             top(Core).eval(M,x) 
> >         end 
> >     eval(m,x) = begin  # none, line 1: 
> >             top(Core).eval(m,x) 
> >         end # none, line 1: 
> >     function f(x) # none, line 1: 
> >         @m 2 
> >     end 
> >     end) 
> > 
> > Also doesn't work. 
> > 
> > On Monday, March 21, 2016 at 7:54:59 AM UTC-7, Tim Holy wrote: 
> > > On Monday, March 21, 2016 09:34:19 AM Stefan Karpinski wrote: 
> > > > Tim, I'm assuming that module must assume that no macros are defined 
> > > 
> > > *and* 
> > > 
> > > > then used within the module body. If that does occur, the only way 
> to do 
> > > > macro expansion correctly is to evaluate the module since the module 
> > > > definition can depend on arbitrary previously evaluated code. 
> > > 
> > > Probably true. I haven't played with it in a long time, but it's 
> possible 
> > > you 
> > > could load the module (so the macros are defined) and then parse the 
> > > file...but 
> > > I can't remember if that works. 
> > > 
> > > Best, 
> > > --Tim 
> > > 
> > > > On Sun, Mar 20, 2016 at 9:00 PM, Tim Holy <[email protected] 
> > > 
> > > <javascript:>> wrote: 
> > > > > It probably needs updating, but 
> > > > > https://github.com/timholy/MacroExpandJL.jl 
> > > > > might help. It lets you macroexpand a whole source file. 
> > > > > 
> > > > > Best, 
> > > > > --Tim 
> > > > > 
> > > > > On Sunday, March 20, 2016 08:53:49 PM Yichao Yu wrote: 
> > > > > > On Sun, Mar 20, 2016 at 8:26 PM,  <[email protected] 
> > > > > > <javascript:>> 
> > > 
> > > wrote: 
> > > > > > > Hi all, 
> > > > > > > 
> > > > > > > I'd like to be able to load in a module, then macroexpand the 
> > > 
> > > whole 
> > > 
> > > > > thing, 
> > > > > 
> > > > > > > then print out the macroexpanded version. 
> > > > > > > 
> > > > > > > This should be a full, recursive macroexpand. 
> > > > > > > 
> > > > > > > I've noticed there is a function called macroexpand that 
> normally 
> > > 
> > > does 
> > > 
> > > > > > > what 
> > > > > > > 
> > > > > > > i want: 
> > > > > > >> macro m(x) 1 end 
> > > > > > > 
> > > > > > > .. 
> > > > > > > 
> > > > > > >> @m(2) 
> > > > > > > 
> > > > > > > 1 
> > > > > > > 
> > > > > > >> macroexpand(:(1 + @m(2))) 
> > > > > > >> 
> > > > > > > :(1 + 1) 
> > > > > > > 
> > > > > > > so that is fine and dandy, but inside a module this doesn't 
> seem 
> > > 
> > > to 
> > > 
> > > > > work: 
> > > > > > >> macroexpand(:( 
> > > > > > >> 
> > > > > > >        module M 
> > > > > > >        macro m(x) 1 end 
> > > > > > >        x = 1 + @m(2) 
> > > > > > >        end 
> > > > > > >        )) 
> > > > > > > : 
> > > > > > > :(module M 
> > > > > > > : 
> > > > > > >     eval(x) = begin  # none, line 2: 
> > > > > > >             top(Core).eval(M,x) 
> > > > > > >         
> > > > > > >         end 
> > > > > > >     
> > > > > > >     eval(m,x) = begin  # none, line 2: 
> > > > > > >             top(Core).eval(m,x) 
> > > > > > >         
> > > > > > >         end # none, line 3: 
> > > > > > >     $(Expr(:macro, :(m(x)), quote  # none, line 3: 
> > > > > > >     1 
> > > > > > > 
> > > > > > > end)) # none, line 4: 
> > > > > > >     x = 1 + @m(2) 
> > > > > > >     end) 
> > > > > > > 
> > > > > > > As you can see in the second to last line, @m(2) is not 
> expanded, 
> > > 
> > > and 
> > > 
> > > > > I'm 
> > > > > 
> > > > > > > confused as to why that is. 
> > > > > > > 
> > > > > > > Ideally, this macroexpanding of a module would allow me to 
> also 
> > > > > > > resolve 
> > > > > > > imports and includes properly, so I could just slurp up a file 
> and 
> > > > > > > dump 
> > > > > > > out 
> > > > > > > the macroexpanded version. 
> > > > > > 
> > > > > > TL;DR this is generally not possible without evaluating the 
> whole 
> > > > > > module. 
> > > > > > 
> > > > > > Macros are executed at parse time and therefore resolved in 
> global 
> > > > > > scope (since local scope doesn't even exist yet) or in another 
> word 
> > > > > > module scope. 
> > > > > > Therefore when doing macro expansion in a new module, the macros 
> > > 
> > > needs 
> > > 
> > > > > > to be resolved in the new module and since there's no way to 
> > > > > > statically know what macros are available in a module you can't 
> do 
> > > > > > that without evaluating the module. 
> > > > > > 
> > > > > > > Thank you! 
> > > > > > > 
> > > > > > > Vishesh 
>
>

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