From dbf0b45fae101e46a398abc3d34e492b960fc416 Mon Sep 17 00:00:00 2001
From: Simon Byrne <simonbyrne@gmail.com>
Date: Sat, 6 Jan 2018 15:14:28 -0800
Subject: [PATCH] allow use of begin blocks inside enum definitions (#25424)

---
 NEWS.md       |  4 ++++
 base/Enums.jl | 14 ++++++++++++++
 test/enums.jl |  8 ++++++++
 3 files changed, 26 insertions(+)

diff --git a/NEWS.md b/NEWS.md
index cb23c20919ccc..b512e2c1b363b 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -40,6 +40,9 @@ New language features
   * Field access via dot-syntax can now be overloaded by adding methods to
     `Base.getproperty` and `Base.setproperty!` ([#1974]).
 
+  * Values for `Enum`s can now be specified inside of a `begin` block when using the
+    `@enum` macro ([#25424]).
+
 Language changes
 ----------------
 
@@ -1162,3 +1165,4 @@ Command-line option changes
 [#25184]: https://github.com/JuliaLang/julia/issues/25184
 [#25231]: https://github.com/JuliaLang/julia/issues/25231
 [#25365]: https://github.com/JuliaLang/julia/issues/25365
+[#25424]: https://github.com/JuliaLang/julia/issues/25424
diff --git a/base/Enums.jl b/base/Enums.jl
index 48c7233178359..3e20f055fe175 100644
--- a/base/Enums.jl
+++ b/base/Enums.jl
@@ -46,6 +46,15 @@ julia> f(apple)
 "I'm a Fruit with value: 1"
 ```
 
+Values can also be specified inside a `begin` block, e.g.
+
+```julia
+@enum EnumName begin
+    value1
+    value2
+end
+```
+
 `BaseType`, which defaults to [`Int32`](@ref), must be a primitive subtype of `Integer`.
 Member values can be converted between the enum type and `BaseType`. `read` and `write`
 perform these conversions automatically.
@@ -69,7 +78,12 @@ macro enum(T, syms...)
     lo = hi = 0
     i = zero(basetype)
     hasexpr = false
+
+    if length(syms) == 1 && syms[1] isa Expr && syms[1].head == :block
+        syms = syms[1].args
+    end
     for s in syms
+        s isa LineNumberNode && continue
         if isa(s, Symbol)
             if i == typemin(basetype) && !isempty(vals)
                 throw(ArgumentError("overflow in value \"$s\" of Enum $typename"))
diff --git a/test/enums.jl b/test/enums.jl
index 068aafff29e49..97f83810920bf 100644
--- a/test/enums.jl
+++ b/test/enums.jl
@@ -148,3 +148,11 @@ let b = IOBuffer()
     seekstart(b)
     @test deserialize(b) === apple
 end
+
+# test block form
+@enum BritishFood begin
+    blackpudding = 1
+    scotchegg    = 2
+    haggis       = 4
+end
+@test Int(haggis) == 4