From faeaff225fc9a1332abfefc4b45cfb55b7569e2d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=BAlio=20Hoffimann?= <julio.hoffimann@gmail.com>
Date: Tue, 14 Jul 2020 22:03:40 -0300
Subject: [PATCH] Add getproperty method

---
 src/composition.jl   | 26 +++++++++++++++-----------
 test/compositions.jl |  6 ++++++
 2 files changed, 21 insertions(+), 11 deletions(-)

diff --git a/src/composition.jl b/src/composition.jl
index 4d96d33..8d87575 100644
--- a/src/composition.jl
+++ b/src/composition.jl
@@ -102,17 +102,21 @@ Names of parts in the composition `c`.
 """
 names(c::Composition{D,SYMS}) where {D,SYMS} = SYMS
 
-# """
-#     getproperty(c, name)
-#
-# Return the value of part with given `name` in the composition `c`.
-# """
-# function getproperty(c::Composition{D,SYMS}, S::Symbol) where {D,SYMS}
-#   for (i, SYM) in enumerate(SYMS)
-#     S == SYM && (return c.parts[i])
-#   end
-#   @error "invalid part $S"
-# end
+"""
+    getproperty(c, name)
+
+Return the value of part with given `name` in the composition `c`.
+"""
+function getproperty(c::Composition{D,SYMS}, S::Symbol) where {D,SYMS}
+  if S == :parts
+    getfield(c, :parts)
+  else
+    for (i, SYM) in enumerate(SYMS)
+      S == SYM && (return c.parts[i])
+    end
+    @error "invalid part name '$S'"
+  end
+end
 
 # ------------
 # IO methods
diff --git a/test/compositions.jl b/test/compositions.jl
index 20b3002..e551932 100644
--- a/test/compositions.jl
+++ b/test/compositions.jl
@@ -14,4 +14,10 @@
   @test names(-c) == names(c)
   @test names(c - c) == names(c)
   @test names(2c) == names(c)
+
+  # get part by name
+  c = Composition(a=3,b=2,c=1)
+  @test c.a == 3
+  @test c.b == 2
+  @test c.c == 1
 end