Syntax: synchronize ppx and camlp4

[hhugo]

the two syntax now generate the same OCaml code (modulo http://caml.inria.fr/mantis/view.php?id=6936)

[Drup]

Oh, nice. Give me tomorrow to review.

[hhugo]

I've used https://github.com/janestreet/camlp4-to-ppx to perform automatic conversion and make sure the two syntax where equivalent.
I'll push my rewriter to https://github.com/janestreet/camlp4-to-ppx this week

[Drup]

This seems good to me.

Do you have an example of bug caused by the non-defined ordering (both in OCaml and in jsoo's ppx prior to this patch) ?

[hhugo]

The undefined ordering only affect side effects aka identifier generation.
It makes diffing post processed ocaml source file with both camlp4 and ppx more painful.

[gasche]

Undefined map ordering is typically an issue when people implement fold (which has an expected iteration order) on top of map using mutable state. (This is why the traversals-generation function of Camlp4 can generate the three of Map, Fold and FoldMap.)

[Drup]

@hhugo You used @@ in the camlp4 code, which should compile on 4.00

[hhugo]

fixed

On Thu, Jul 23, 2015 at 2:32 PM, Gabriel Radanne notifications@github.com
wrote:

@hhugo https://github.com/hhugo You used @@ in the camlp4 code, which
should compile on 4.00

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Reply to this email directly or view it on GitHub
#344 (comment).

[hhugo]

see janestreet/camlp4-to-ppx@d2b55dc for automatic rewrite to ppx