Experiment with a virtual machine for regexes (#41)

We implement a series of small C++ experiments to get a better
understanding of how a virtual machine for Regexes might work. We leave
the code in the repository so that future developers can also get
familiar with the technique.

experimental/re/CMakeLists.txt

@@ -0,0 +1,29 @@
+cmake_minimum_required(VERSION 3.19)
+project(re)
+
+set(CMAKE_CXX_STANDARD 11)
+
+# NOTE (mristin):
+# See: https://crascit.com/2015/03/28/enabling-cxx11-in-cmake/
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_EXTENSIONS OFF)
+
+if (MSVC)
+    add_compile_options(/W4 /WX)
+else ()
+    add_compile_options(
+            -Wall
+            -Wextra
+            -Wpedantic
+            -Wno-unknown-pragmas
+            -Wno-unused-parameter
+            -Wno-implicit-fallthrough
+            -Wno-switch
+    )
+endif ()
+
+
+add_executable(
+        playground
+        playground.cpp
+)