use isdefined for iszero instead of VERSION check (#109)

tkelman · lbenet · commit d4f0c20a4db8 · 2017-05-25T12:21:25.000-05:00
* use isdefined for iszero instead of VERSION check

* only need Compat 0.17 for abstract type
diff --git a/REQUIRE b/REQUIRE
@@ -1,2 +1,2 @@
 julia 0.5
-Compat 0.19.0
+Compat 0.17.0
diff --git a/src/TaylorSeries.jl b/src/TaylorSeries.jl
@@ -20,7 +20,7 @@ module TaylorSeries
 
 using Compat
 
-if VERSION ≤ v"0.6.0-dev"
+if !isdefined(Base, :iszero)
     import Compat: iszero
     export iszero
 else
