From ef6a1c9ea39a594db1b6454aa100521a3d3557f8 Mon Sep 17 00:00:00 2001
From: Simon Kornblith <simon@simonster.com>
Date: Fri, 14 Aug 2015 15:23:12 -0400
Subject: [PATCH] Add macro for conditionally choosing code based on Julia
 version

---
 src/Compat.jl    | 10 ++++++++++
 test/runtests.jl |  6 ++++++
 2 files changed, 16 insertions(+)

diff --git a/src/Compat.jl b/src/Compat.jl
index 56eb02f61..de8f88c91 100644
--- a/src/Compat.jl
+++ b/src/Compat.jl
@@ -566,4 +566,14 @@ if VERSION < v"0.4.0-dev+6578"
     export ≈, ≉
 end
 
+macro julia_geq(ex)
+    (Base.Meta.isexpr(ex, :if) && length(ex.args) == 3) ||
+        throw(ArgumentError("invalid syntax"))
+    version = ex.args[1]
+    (Base.Meta.isexpr(version, :macrocall) && length(version.args) == 2 && version.args[1] === symbol("@v_str")) ||
+        throw(ArgumentError("invalid syntax"))
+    VERSION >= convert(VersionNumber, version.args[2]) ? esc(ex.args[2]) : esc(ex.args[3])
+end
+export @julia_geq
+
 end # module
diff --git a/test/runtests.jl b/test/runtests.jl
index 9e6cbf8f7..ae89e7983 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -420,3 +420,9 @@ Compat.@irrational mathconst_one 1.0 big(1.)
 @test [1,2,3] ≈ [1,2,3+1e-9]
 @test [0,1] ≈ [1e-9, 1]
 @test [0,1] ≉ [1e-3, 1]
+
+passed = false
+@julia_geq v"0.1-" ? (passed = true) : error("@julia_geq test failed")
+@test passed
+passed = false
+@julia_geq v"100" ? error("@julia_geq test failed") : (passed = true)