From ac374087b38718ccf2252c4a26340e3e391e7e77 Mon Sep 17 00:00:00 2001
From: Mike J Innes <mike.j.innes@gmail.com>
Date: Fri, 16 Dec 2016 15:54:15 +0000
Subject: [PATCH] load tf lazily to speed up load time

---
 src/backend/backend.jl | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/src/backend/backend.jl b/src/backend/backend.jl
index 104272bf..372148f9 100644
--- a/src/backend/backend.jl
+++ b/src/backend/backend.jl
@@ -1,5 +1,11 @@
-# TODO: load backends lazily
-
-include("tensorflow/tensorflow.jl")
-using .TF
 export tf
+
+function loadtf()
+  isdefined(Flux, :TF) && return
+  @eval include(joinpath(dirname($@__FILE__), "tensorflow/tensorflow.jl"))
+end
+
+function tf(args...)
+  loadtf()
+  TF.tf(args...)
+end