From 2efd3407ac6703d3914f239a378620a93a7980a8 Mon Sep 17 00:00:00 2001
From: karl <karl.bittner@hexaquo.at>
Date: Fri, 5 Mar 2021 14:14:27 +0100
Subject: [PATCH] Basic implementation aside from resizing done

---
 .clang-format |  15 ++++----
 Vector.cpp    |   6 ---
 Vector.h      | 102 +++++++++++++++++++++++++++++++++++++++++++++++++-
 main.cpp      |  44 +++++++++++++++++++++-
 4 files changed, 151 insertions(+), 16 deletions(-)
 delete mode 100644 Vector.cpp

diff --git a/.clang-format b/.clang-format
index a63e137..1e5484c 100644
--- a/.clang-format
+++ b/.clang-format
@@ -1,13 +1,14 @@
 ---
 BasedOnStyle: LLVM
-AllowShortBlocksOnASingleLine: 'true'
-AllowShortCaseLabelsOnASingleLine: 'true'
-AllowShortFunctionsOnASingleLine: Inline
+AllowShortBlocksOnASingleLine: false
+AllowShortCaseLabelsOnASingleLine: true
+AllowShortFunctionsOnASingleLine: None
 AllowShortIfStatementsOnASingleLine: WithoutElse
 AllowShortLambdasOnASingleLine: Inline
-AllowShortLoopsOnASingleLine: 'false'
-AlwaysBreakBeforeMultilineStrings: 'true'
-IndentWidth: '4'
-ColumnLimit: 100
+AllowShortLoopsOnASingleLine: false
+AlwaysBreakBeforeMultilineStrings: true
+AlwaysBreakTemplateDeclarations: true
+IndentWidth: 4
+ColumnLimit: 80
 
 ...
diff --git a/Vector.cpp b/Vector.cpp
deleted file mode 100644
index 670384a..0000000
--- a/Vector.cpp
+++ /dev/null
@@ -1,6 +0,0 @@
-#include "Vector.h"
-#include <iostream>
-
-Vector::Vector() {
-    std::cout << "Vector created" << std::endl;
-}
diff --git a/Vector.h b/Vector.h
index abdb1a7..e5dd201 100644
--- a/Vector.h
+++ b/Vector.h
@@ -1,4 +1,104 @@
+#pragma once
+#include <algorithm>
+#include <cassert>
+#include <iostream>
+
+template <class T>
 class Vector {
   public:
-    Vector();
+    // Constructor
+    Vector(unsigned int capacity = 10)
+        : capacity(capacity), element_count(0), data(new T[capacity]) {
+        std::cout << "Vector created" << std::endl;
+    }
+
+    // Copy Constructor
+    Vector(const Vector &other)
+        : capacity(other.capacity), element_count(other.element_count),
+          data(new T[capacity]) {
+        // `std::copy` is used because it is more flexible than `std::memcpy`,
+        // and the compiler will replace it with `memcpy` anyway if appropriate,
+        // so there is no performance loss.
+        std::copy(other.data, other.data + element_count, data);
+    }
+
+    // Move Constructor using the copy-and-swap-idiom
+    Vector(Vector &&other) : data(new T[capacity]) {
+        swap(*this, other);
+    }
+
+    // Copy Assignment Operator using the copy-and-swap-idiom
+    // Since this takes a value rather than a const reference due to
+    // copy-and-swap, this is also the Move Assignment Operator
+    Vector &operator=(Vector other) {
+        swap(*this, other);
+
+        return *this;
+    }
+
+    // Destructor
+    ~Vector() {
+        delete[] data;
+
+        std::cout << "Vector deleted" << std::endl;
+    }
+
+    // Bracket Operator
+    T &operator[](unsigned int position) const {
+        return at(position);
+    }
+
+    // Swap function for the copy-and-swap idiom.
+    // See also:
+    // https://stackoverflow.com/questions/3279543/what-is-the-copy-and-swap-idiom
+    // The `friend` keyword is used so it is found through ADL.
+    friend void swap(Vector &first, Vector &second) {
+        // Enable ADL (good practice)
+        using std::swap;
+
+        swap(first.capacity, second.capacity);
+        swap(first.element_count, second.element_count);
+        swap(first.data, second.data);
+    }
+
+    void push_back(const T &element) {
+        if (element_count >= capacity) {
+            // TODO: Increase capacity!
+        }
+
+        // Use placement new to directly use pre-allocated memory
+        new (data + element_count) T(element);
+        element_count++;
+    }
+
+    void erase(unsigned int position) {
+        assert(position < element_count);
+
+        std::copy_backward(data + position + 1, data + element_count,
+                           data + element_count - 1);
+
+        element_count--;
+    }
+
+    unsigned int size() const {
+        return element_count;
+    }
+
+    unsigned int length() const {
+        return capacity;
+    }
+
+    T &at(unsigned int position) const {
+        assert(position < element_count);
+        return data[position];
+    }
+
+    void reserve(unsigned int);
+
+    void resize(unsigned int);
+
+  private:
+    T *data;
+    unsigned int element_count;
+    unsigned int capacity;
 };
diff --git a/main.cpp b/main.cpp
index 8f8e0b8..364d456 100644
--- a/main.cpp
+++ b/main.cpp
@@ -1,6 +1,46 @@
 #include "Vector.h"
 #include <iostream>
 
-int main() {
-    Vector vector;
+void print_float_vector(const Vector<float> &v) {
+    for (int i = 0; i < v.size(); i++) {
+        std::cout << v[i] << ", ";
+    }
+    std::cout << std::endl;
+}
+
+int main() {
+    Vector<float> vector1;
+
+    vector1.push_back(0.5);
+    vector1.push_back(0.7);
+    vector1.push_back(1.2);
+    vector1.push_back(2.0);
+    vector1.push_back(3.0);
+
+    std::cout << "Before erase at 2" << std::endl;
+    print_float_vector(vector1);
+
+    vector1.erase(2);
+
+    std::cout << "After erase at 2" << std::endl;
+    print_float_vector(vector1);
+
+    Vector<float> vector2 = std::move(vector1);
+
+    std::cout << "After std::move" << std::endl;
+    print_float_vector(vector2);
+
+    Vector<float> vector3 = vector2;
+
+    std::cout << "After copy construction" << std::endl;
+    print_float_vector(vector2);
+    print_float_vector(vector3);
+
+    Vector<float> vector4;
+    vector4.push_back(7353.0);
+    vector4 = vector3;
+
+    std::cout << "After copy assignment" << std::endl;
+    print_float_vector(vector3);
+    print_float_vector(vector4);
 }