helper templates static, eval and emit for easier compile-time code evaluation

lib/system.nim

@@ -2213,6 +2213,20 @@ proc shallow*(s: var string) {.noSideEffect, inline.} =
     var s = cast[PGenericSeq](s)
     s.reserved = s.reserved or seqShallowFlag
 
+template static*(e: expr): expr =
+  ## evaluates a given expression `e` at compile-time
+  ## even if it has side effects
+  block:
+    const res = e
+    res
+
+template eval*(blk: stmt): stmt =
+  ## executes a block of code at compile time just as if it was a macro
+  ## optonally, the block can return an AST tree that will replace the 
+  ## eval expression
+  block:
+    macro payload(x: stmt): stmt = blk
+    payload()
 
 when defined(initDebugger):
   initDebugger()