refactoring: fewer global variables

compiler/pluginsupport.nim

@@ -8,40 +8,26 @@
 #
 
 ## Plugin support for the Nim compiler. Right now plugins
-## need to be built with the compiler only: plugins using 
+## need to be built with the compiler only: plugins using
 ## DLLs or the FFI will not work.
 
 import ast, semdata, idents
 
 type
   Transformation* = proc (c: PContext; n: PNode): PNode {.nimcall.}
-  Plugin = ref object
-    fn, module, package: PIdent
+  Plugin* = tuple
+    package, module, fn: string
     t: Transformation
-    next: Plugin
 
-proc pluginMatches(p: Plugin; s: PSym): bool =
-  if s.name.id != p.fn.id:
+proc pluginMatches*(ic: IdentCache; p: Plugin; s: PSym): bool =
+  if s.name.id != ic.getIdent(p.fn).id:
     return false
   let module = s.skipGenericOwner
   if module == nil or module.kind != skModule or
-      module.name.id != p.module.id:
+      module.name.id != ic.getIdent(p.module).id:
     return false
   let package = module.owner
   if package == nil or package.kind != skPackage or
-      package.name.id != p.package.id:
+      package.name.id != ic.getIdent(p.package).id:
     return false
   return true
-
-var head: Plugin
-
-proc getPlugin*(fn: PSym): Transformation =
-  var it = head
-  while it != nil:
-    if pluginMatches(it, fn): return it.t
-    it = it.next
-
-proc registerPlugin*(package, module, fn: string; t: Transformation) =
-  let oldHead = head
-  head = Plugin(fn: getIdent(fn), module: getIdent(module),
-                 package: getIdent(package), t: t, next: oldHead)