From 4bd69ebbd83c5fa3b625dde28f8f170eb9e532ac Mon Sep 17 00:00:00 2001
From: laurens <miers132@gmail.com>
Date: Sun, 11 Oct 2020 16:42:00 +0200
Subject: [PATCH] Add state pattern: Types-way

---
 state_pattern_types/Cargo.toml  |  9 ++++++
 state_pattern_types/src/main.rs | 55 +++++++++++++++++++++++++++++++++
 2 files changed, 64 insertions(+)
 create mode 100644 state_pattern_types/Cargo.toml
 create mode 100644 state_pattern_types/src/main.rs

diff --git a/state_pattern_types/Cargo.toml b/state_pattern_types/Cargo.toml
new file mode 100644
index 0000000..c66b710
--- /dev/null
+++ b/state_pattern_types/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "state_pattern_types"
+version = "0.1.0"
+authors = ["laurens <miers132@gmail.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
diff --git a/state_pattern_types/src/main.rs b/state_pattern_types/src/main.rs
new file mode 100644
index 0000000..14ed679
--- /dev/null
+++ b/state_pattern_types/src/main.rs
@@ -0,0 +1,55 @@
+pub struct DraftPost {
+    content: String,
+}
+
+pub struct PendingReviewPost {
+    content: String,
+}
+
+pub struct Post {
+    content: String,
+}
+
+impl DraftPost {
+    pub fn add_text(&mut self, text: &str) {
+        self.content.push_str(text);
+    }
+
+    pub fn request_review(self) -> PendingReviewPost {
+        PendingReviewPost {
+            content: self.content,
+        }
+    }
+}
+
+impl PendingReviewPost {
+    pub fn approve(self) -> Post {
+        Post {
+            content: self.content,
+        }
+    }
+}
+
+impl Post {
+    pub fn new() -> DraftPost {
+        DraftPost {
+            content: String::new(),
+        }
+    }
+
+    pub fn content(&self) -> &str {
+        &self.content
+    }
+}
+
+fn main() {
+    let mut post = Post::new();
+
+    post.add_text("I ate a salad for lunch today");
+
+    let post = post.request_review();
+
+    let post = post.approve();
+
+    assert_eq!("I ate a salad for lunch today", post.content());
+}