fixes #120

lib/core/macros.nim

@@ -234,16 +234,14 @@ proc getAst*(macroOrTemplate: expr): PNimrodNode {.magic: "ExpandToAst".}
   ##   macro FooMacro() =
   ##     var ast = getAst(BarTemplate())
 
-template emit*(s: expr): stmt =
+template emit*(e: expr[string]): stmt =
   ## accepts a single string argument and treats it as nimrod code
   ## that should be inserted verbatim in the program
   ## Example:
   ##
   ##   emit("echo " & '"' & "hello world".toUpper & '"')
   ##
-  block:
-    const evaluated = s
-    eval: result = evaluated.parseStmt
+  eval: result = e.parseStmt
 
 proc expectKind*(n: PNimrodNode, k: TNimrodNodeKind) {.compileTime.} =
   ## checks that `n` is of kind `k`. If this is not the case,

lib/system.nim

@@ -2349,9 +2349,8 @@ template eval*(blk: stmt): stmt =
   ## executes a block of code at compile time just as if it was a macro
   ## optionally, the block can return an AST tree that will replace the 
   ## eval expression
-  block:
-    macro payload(x: stmt): stmt = blk
-    payload()
+  macro payload: stmt {.gensym.} = blk
+  payload()
 
 proc insert*(x: var string, item: string, i = 0) {.noSideEffect.} = 
   ## inserts `item` into `x` at position `i`.