From 274f0429de281db447507ba2e9433acf68cd82f7 Mon Sep 17 00:00:00 2001
From: Emery Hemingway <ehmry@posteo.net>
Date: Wed, 30 Jun 2021 10:47:54 +0200
Subject: [PATCH] macros: inject more getCurrentFacet

---
 src/syndicate/macros.nim | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/src/syndicate/macros.nim b/src/syndicate/macros.nim
index a48f0e4..a47b220 100644
--- a/src/syndicate/macros.nim
+++ b/src/syndicate/macros.nim
@@ -39,6 +39,7 @@ template stopIf*(cond, body: untyped): untyped =
   discard getCurrentFacet().addDataflow do (facet: Facet):
     if cond:
       facet.stop do (facet: Facet):
+        proc getCurrentFacet(): Facet {.inject, used.} = facet
         body
 
 template send*(class: RecordClass; fields: varargs[Preserve,
@@ -62,11 +63,9 @@ proc assertionForRecord(class: RecordClass; doHandler: NimNode): NimNode =
         result.add newCall("init", ident"Capture", newCall("init",
             ident"Discard"))
 
-proc callbackForEvent(event: EventKind; class: RecordClass; doHandler: NimNode;
-    assertion: NimNode): NimNode =
+proc callbackForEvent(event: EventKind; class: RecordClass; doHandler: NimNode): NimNode =
   ## Generate a procedure that checks an event kind, unpacks the fields of `class` to match the
   ## parameters of `doHandler`, and calls the body of `doHandler`.
-  # TODO: the assertion parameter is just for tracing.
   let formalArgs = doHandler[3]
   if formalArgs.len.pred != class.arity:
     error($formalArgs.repr & " does not match record class " & $class, doHandler)
@@ -105,6 +104,11 @@ proc callbackForEvent(event: EventKind; class: RecordClass; doHandler: NimNode;
     body = newStmtList(
       newCall("assert",
           infix(newCall("len", recSym), "==", newLit(captureCount))),
+      newProc(
+          name = ident"getCurrentFacet",
+          params = [ ident"Facet" ],
+          body = scriptFacetSym,
+          pragmas = newNimNode(nnkPragma).add(ident"inject").add(ident"used")),
       letSection,
       doHandler[6]
     )
@@ -131,7 +135,7 @@ proc callbackForEvent(event: EventKind; class: RecordClass; doHandler: NimNode;
 proc onEvent(event: EventKind; class: RecordClass; doHandler: NimNode): NimNode =
   let
     assertion = assertionForRecord(class, doHandler)
-    handler = callbackForEvent(event, class, doHandler, assertion)
+    handler = callbackForEvent(event, class, doHandler)
     handlerSym = handler[0]
   result = quote do:
     `handler`
@@ -154,7 +158,7 @@ macro onMessage*(class: static[RecordClass]; doHandler: untyped) =
 template assert*(class: RecordClass; field: untyped): untyped =
   mixin getCurrentFacet
   let facet = getCurrentFacet()
-  discard facet.addEndpoint do (facet: Facet) -> EndpointSpec:
+  discard facet.addEndpoint do (_: Facet) -> EndpointSpec:
     let a = init(class, getPreserve(field))
     result.assertion = some(a)
 
@@ -168,11 +172,11 @@ template field*(F: untyped; T: typedesc; initial: T): untyped =
 template spawn*(name: string; spawnBody: untyped): untyped =
   mixin getCurrentFacet
   spawn(getCurrentFacet(), name) do (spawnFacet: Facet):
-    proc getCurrentFacet(): Facet {.inject.} = spawnFacet
+    proc getCurrentFacet(): Facet {.inject, used.} = spawnFacet
     spawnBody
 
 template syndicate*(name: string; dataspaceBody: untyped): untyped =
   proc bootProc(rootFacet: Facet) =
-    proc getCurrentFacet(): Facet {.inject.} = rootFacet
+    proc getCurrentFacet(): Facet {.inject, used.} = rootFacet
     dataspaceBody
   waitFor bootModule(name, bootProc)