I skimmed through the Parrot executable code a few days ago and gathered up a list of the libparrot functions called from it. This is going to help us break the embedding API work into a series of waves that we can tackle one at a time. I like working on big tasks in small chunks anyway, but Parrot’s monthly release schedule basically mandates that we have certain windows in which we can deliver incremental improvements. It’s my number one priority to ensure that Parrot’s users get these API improvements as quickly as we can possibly manage.

The first wave, which got this entire train rolling, was inspired by shockwave’s comments to a prior post where he talked about his difficulties with the embeddng API. I already have a function in place to resolve the one problem he mentioned specifically. That function, Parrot_load_bytecode_file needs to be renamed and moved to a new file of official embedding API functions. This will certainly be in place by the 2.10 release on November 16th. The big result that comes from this first wave is the creation of the Product Management team and the Embedding API task force. We’re also using this opportunity to do some proper, forward-thinking design, so th

In my mind the second wave will involve fixing the Parrot executable so that it only interacts with libparrot through actual API function calls. This is going to be a little bit more tricky, but I have full confidence that we can get it done by the 2.11 release on December 21st.

I have prepared a list of all libparrot functions that are called from the Parrot executable, and a list of all structure fields which it pokes into directly. All of these will have to be converted to new API calls (some of which may be nearly identical to the previous API functions).

First, two macros are called:


I’m only vaguely familiar with the purposes of these macros, though I don’t think they are really used by Parrot as it currently exists. I’m not sure that we need them right now (though it probably doesn’t hurt). I think we should probably turn these into functions instead of macros. The NCI module from other interpreters won’t be able to bind to a macro, for instance.

Next, the functions that are called:


All these functions will, at the very least, be renamed to Parrot_api_... and in many cases will change substantially to include some of the mechanisms and design points that I talked about in yesterday’s post.

Finally, the structures that are directly touched:


The deprecation policy requires that all pointers and structures be considered opaque, so we absolutely can not be exposing them like this. It doesn’t matter what the interface is, so much as it matters that we have any interface. The current situation is unmaintanable and unacceptable.

The third wave is a little bit more nebulous, but at the same time it is probably the most important: we need to allow embedding applications to work directly with PMC and STRING types, and expose all the necessary operations on those types. I don’t know what the timeframe is going to be for this third wave, we need to gather a lot more information, feedback, and user requirements before we can even start designing this portion of the interface.