From 15f7094fde2a5677b6566dfa1a883237cac676ec Mon Sep 17 00:00:00 2001
From: Andrea Ferretti <ferrettiandrea@gmail.com>
Date: Thu, 22 Sep 2016 12:07:36 +0200
Subject: [PATCH] Added a dump macro for debugging

---
 lib/pure/future.nim    | 21 +++++++++++++++++++++
 tests/macros/tdump.nim | 13 +++++++++++++
 2 files changed, 34 insertions(+)
 create mode 100644 tests/macros/tdump.nim

diff --git a/lib/pure/future.nim b/lib/pure/future.nim
index 67975cfcb..2a6d29933 100644
--- a/lib/pure/future.nim
+++ b/lib/pure/future.nim
@@ -177,3 +177,24 @@ macro `[]`*(lc: ListComprehension, comp, typ: untyped): untyped =
               newIdentNode("@"),
               newNimNode(nnkBracket))),
           result))))
+
+
+macro dump*(x: typed): untyped =
+  ## Dumps the content of an expression, useful for debugging.
+  ## It accepts any expression and prints a textual representation
+  ## of the tree representing the expression - as it would appear in
+  ## source code - together with the value of the expression.
+  ##
+  ## As an example,
+  ##
+  ## .. code-block:: nim
+  ##   let
+  ##     x = 10
+  ##     y = 20
+  ##   dump(x + y)
+  ##
+  ## will print ``x + y = 30``.
+  let s = x.toStrLit
+  let r = quote do:
+    debugEcho `s`, " = ", `x`
+  return r
\ No newline at end of file
diff --git a/tests/macros/tdump.nim b/tests/macros/tdump.nim
new file mode 100644
index 000000000..e4c14dc6b
--- /dev/null
+++ b/tests/macros/tdump.nim
@@ -0,0 +1,13 @@
+discard """
+  output: '''x = 10
+x + y = 30
+'''
+"""
+
+import future
+
+let
+  x = 10
+  y = 20
+dump x
+dump(x + y)
\ No newline at end of file