Update README.md

README.md

@@ -3,4 +3,53 @@
 
 # EasyIterator
 
-Work in progress: simple C++ iterator creation
+EasyIterator aims to be a zero-cost C++17 iterator library that simplifies iterator creation.
+It adds well-known iterators from other languages to C++, such as `range`, `zip` and `enumerate`. 
+
+## Example
+
+### Iteration
+
+```cpp
+using namespace easy_iterator;
+
+std::vector<int> integers(10);
+std::vector<std::string> strings(integers.size());
+
+for (auto i: range(integers.size())) {
+  integers[i] = i*i;
+}
+
+for (auto [i, v, s]: zip(range(integers.size()), integers, strings)) {
+  s = std::to_string(i) + "^2 = " + std::to_string(v);
+}
+
+for (auto [i, s]: enumerate(strings)) {
+  std::cout << "strings[" << i << "] = \"" << s << "\"" << std::endl;
+}
+```
+
+### Simple iterator creation
+
+```cpp
+struct Fibonacci {
+  unsigned current = 0;
+  unsigned next = 1;
+
+  void advance() {
+    auto tmp = next;
+    next += current;
+    current = tmp;
+    return true;
+  }
+  
+  unsigned value() {
+    return current;
+  }
+};
+
+for (auto [i,v]: enumerate(MakeIterable<Fibonacci>())){
+  std::cout << "Fib_" << i << "\t= " << v << std::endl;
+  if (i > 10) break;
+}
+```