Summary:
Add support to ppx_trace to rewrite `[%trace]` into a call to the
corresponding `Trace` function:
```lang=ocaml
val trace :
?call:(pf -> unit)
-> ?retn:(pf -> 'a -> unit)
-> ?rais:(pf -> exn -> Printexc.raw_backtrace -> unit)
-> string
-> string
-> (unit -> 'a)
-> 'a
(** [trace ~call ~retn ~rais mod_name fun_name k] either simply invokes
[k ()], when not enabled, or else increases the indentation level and
emits the [call] message, then invokes [k ()], then decreases the
indentation level and either emits the [retn] or [rais] message,
depending on whether [k ()] returned normally or exceptionally. *)
```
The main motivation over the existing `Trace.call` and `Trace.retn` is
that by packaging them together, unhandled exceptions can be treated
better.
Reviewed By: jvillard
Differential Revision: D23636200
fbshipit-source-id: f61c267fd
Summary:
Construct the identity function explicitly instead of relying on the
`Stdlib.Fun.id` name, which can be problematic depending on compiler
version and which modules have been `open`ed.
Reviewed By: jvillard
Differential Revision: D23636204
fbshipit-source-id: 2fb644c18
Summary:
The expansion of the `[%debug]` extension point is simple and fits
into the pattern supported by `Ppxlib.Extension`. This diff simplifies
the mapper implementing the rest of the trace expansion by moving the
expansion of debug into a separate
`Ppxlib.Context_free.Rule.extension` rule.
Reviewed By: jvillard
Differential Revision: D23636201
fbshipit-source-id: 847c258fd
Summary:
Use `Ppxlib.Ast_traverse.map` instead of
`Ppxlib.Selected_ast.Ast.Ast_mapper` which is included from
`Migrate_parsetree` since `Ppxlib.Selected_ast.Ast` reexports one of
the `Migrate_parsetree.Versions` modules. This change is needed to be
compatible with (ocaml-migrate-parsetree 2.0 and) ppxlib 0.16 since it
no longer re-exports the `Ast_mapper` module from
`Migrate_parsetree`. This ppxlib change is one of the headline
simplification enablers noted in the (announcement of
ocaml-migrate-parsetree
2.0)[https://discuss.ocaml.org/t/ocaml-migrate-parsetree-2-0-0/5991].
Reviewed By: jvillard
Differential Revision: D23636203
fbshipit-source-id: 71e24b46b
Summary:
Passing info that affects the build through environment variables is
bad since it is not very visible, e.g. in log files. Also, those
settings are not recorded in .merlin files, leading to merlin using
the default configuration.
This diff changes ppx_trace to use a 'cookie' instead of an
environment variable, and configures dune to set this cookie based on
the selected profile. This has the benefit of using command line
arguments such as `--cookie 'ppx_trace_enabled="1"'` which appear in
build logs and .merlin files.
Reviewed By: jvillard
Differential Revision: D20590515
fbshipit-source-id: d2daceaa3
Summary:
It seems to currently not be possible to make dune `preprocess`
stanzas vary across contexts, without essentially generating the dune
files. A consequence is that it is not possible to pass
context-dependent command line arguments to ppx rewriters. So add
support for an environment variable instead.
Reviewed By: jvillard
Differential Revision: D20322871
fbshipit-source-id: f3f3ea413
Summary:
Move files, adjust build system, etc.
This also separates out the ppx_trace conditional compilation debug
tracing machinery into an independent package and library.
Reviewed By: jvillard
Differential Revision: D20322876
fbshipit-source-id: a50522462
Josh Berdine