using compiler

abstract class MagicPlugin : DslPlugin
{
  new make(Compiler c) : super(c) {}
  
  override Expr compile(DslExpr expr)
  {
    loc := expr.loc
    doMagic(type(loc, expr), slot(loc, expr), loc, expr.src)
    return LiteralExpr.makeNull(expr.loc, ns)
  }
 
  private CompilationUnit unit(Loc loc)
  {
    units.find { it.loc.file == loc.file }
  }
  
  //facet qname
  private static const Str fn := "magic::Magic" 
  private TypeDef type(Loc loc, Expr expr)
  {
    unit(loc).types.find 
    { 
      (it.facets?.any 
      {
        it.vals.contains(expr) 
      } ?: false) ||
      it.slotDefs.any
      {
        it.facets?.any
        {
          it.vals.contains(expr)
        } ?: false
      } 
    }
  }
  
  
  private SlotDef? slot(Loc loc, Expr expr)
  {
    type(loc, expr).slotDefs.find
    {
      it.facets?.any
      {
        it.vals.contains(expr)
      } ?: false
    }
  }
  **
  ** type - type definition of enclosing type
  ** method - method definition. If method is null,
  ** then magic applied to type, otherwise - to method
  ** 
  abstract Void doMagic(TypeDef type, SlotDef? slot, Loc loc, Str src)
}