From d623eb6805918ada63c7ef6a886737bda747ce98 Mon Sep 17 00:00:00 2001
From: Fredrik Ekre <ekrefredrik@gmail.com>
Date: Mon, 14 Mar 2022 13:59:16 +0100
Subject: [PATCH] Allow initialization of values from preview enum instances.

---
 src/EnumX.jl     | 8 +++++++-
 test/runtests.jl | 8 ++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/src/EnumX.jl b/src/EnumX.jl
index ccbb1b2..e167a2b 100644
--- a/src/EnumX.jl
+++ b/src/EnumX.jl
@@ -43,7 +43,13 @@ function enumx(_module_, name, args...)
             end
             sym = s
         elseif s isa Expr && s.head === :(=) && s.args[1] isa Symbol && length(s.args) == 2
-            nx = Core.eval(_module_, s.args[2])
+            if s.args[2] isa Symbol &&
+               (i = findfirst(x -> x.first === s.args[2], name_value_map); i !== nothing)
+                @assert name_value_map[i].first === s.args[2]
+                nx = name_value_map[i].second
+            else
+                nx = Core.eval(_module_, s.args[2])
+            end
             if !(nx isa Integer && typemin(baseT) <= nx <= typemax(baseT))
                 panic(
                     "invalid value for Enum $(modname){$(baseT)}: " *
diff --git a/test/runtests.jl b/test/runtests.jl
index 041ff45..97fd280 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -4,6 +4,8 @@ using EnumX, Test
 
 const T16 = Int16
 getInt64() = Int64
+const Elppa = -1
+const Ananab = -1
 
 @testset "EnumX" begin
 
@@ -192,4 +194,10 @@ let io = IOBuffer()
     @test str == "FruitDup.Apple = FruitDup.Banana = 0"
 end
 
+
+# Initialize with previous instance name
+@enumx FruitPrev Elppa Banana=Elppa Orange=Ananab
+@test FruitPrev.Elppa === FruitPrev.Banana === FruitPrev.Type(0)
+@test FruitPrev.Orange === FruitPrev.Type(-1)
+
 end # testset