Use string interpolation for the whole description string

Yurii Samsoniuk · web-flow · commit 8f57fbb8635d · 2017-02-13T09:49:30.000+01:00
diff --git a/Binary Tree/BinaryTree.swift b/Binary Tree/BinaryTree.swift
@@ -21,7 +21,7 @@ extension BinaryTree: CustomStringConvertible {
   public var description: String {
     switch self {
     case let .node(left, value, right):
-      return "value: \(value), left = [" + left.description + "], right = [" + right.description + "]"
+      return "value: \(value), left = [\(left.description)], right = [\(right.description)]"
     case .empty:
       return ""
     }

Original file line number	Diff line number	Diff line change
`@@ -21,7 +21,7 @@ extension BinaryTree: CustomStringConvertible {`
`21`	`21`	`public var description: String {`
`22`	`22`	`switch self {`
`23`	`23`	`case let .node(left, value, right):`
`24`		`- return "value: \(value), left = [" + left.description + "], right = [" + right.description + "]"`
	`24`	`+ return "value: \(value), left = [\(left.description)], right = [\(right.description)]"`
`25`	`25`	`case .empty:`
`26`	`26`	`return ""`
`27`	`27`	`}`