[pypy-dev] setting attribute of JitHookInterface instance

[Magnus Morton]

Hi Armin, 

Thanks for looking into this. Is this pre-translation code a general thing possible with any RPython based compiler, or is it very PyPy specific? 

Cheers,
Magnus

> On 16 Mar 2016, at 08:45, Armin Rigo <arigo at tunes.org> wrote:
> 
> Hi Magnus,
> 
> On 16 March 2016 at 01:37, Magnus Morton <m at magnusmorton.com> wrote:
>> You can recreate it in PyPy by putting the following two lines pretty much anywhere in interpreter level code other than the setup_after_space_initialization methods
>> 
>> from pypy.module.pypyjit.hooks import pypy_hooks
>> pypy_hooks.foo = “foo”
>> 
>> What I can’t understand is what is special about the setup_after_space_initialization methods that makes it work there.
> 
> Reproduced and figured it out.  Added some docs in eda9fd6a0601:
> 
> +    # WARNING: You should make a single prebuilt instance of a subclass
> +    # of this class.  You can, before translation, initialize some
> +    # attributes on this instance, and then read or change these
> +    # attributes inside the methods of the subclass.  But this prebuilt
> +    # instance *must not* be seen during the normal annotation/rtyping
> +    # of the program!  A line like ``pypy_hooks.foo = ...`` must not
> +    # appear inside your interpreter's RPython code.
> 
> In PyPy, setup_after_space_initialization() is not RPython (which means
> it is executed before translation).
> 
> 
> A bientôt,
> 
> Armin.