Added version check

src/cs-mic-cli/Functions/PrintVariables.cs

@@ -59,7 +59,7 @@ namespace cs_mic_cli.Functions
                 Console.WriteLine("{0}. {1} {2} = {3}", variableIndex++, variable.Type, variable.Name, displayValue);
             }
 
-            return FunctionValue.NONE;
+            return FunctionValue.ZERO;
         }
     }
 }

src/cs-mic-cli/Functions/Version.cs

@@ -0,0 +1,100 @@
+using CSMic;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace cs_mic_cli.Functions
+{
+    internal class Version : ICodedFunction
+    {
+        private static Lazy<string> versionCLI = new Lazy<string>(() =>
+        {
+            string version = GetVersion(Assembly.GetExecutingAssembly());
+
+            return string.Format("{0,-20} {1}", "CLI", version);
+        });
+
+        private static Lazy<string> versionCSMIC = new Lazy<string>(() =>
+        {
+            string version = GetVersion(typeof(CSMic.InputInterpreter).Assembly);
+
+            return string.Format("{0,-20} {1}", "CS-MIC", version);
+        });
+
+        private static Lazy<string> versionStandardLibrary = new Lazy<string>(() =>
+        {
+            string version = GetVersion(typeof(CSMic.StandardLibrary.Initializer).Assembly);
+
+            return string.Format("{0,-20} {1}", "Standard Library", version);
+        });
+
+        public static string VersionCLI
+        {
+            get
+            {
+                return versionCLI.Value;
+            }
+        }
+
+        public static string VersionCSMIC
+        {
+            get
+            {
+                return versionCSMIC.Value;
+            }
+        }
+
+        public static string VersionStandardLibrary
+        {
+            get
+            {
+                return versionStandardLibrary.Value;
+            }
+        }
+
+        public string Name
+        {
+            get
+            {
+                return "version";
+            }
+        }
+
+        public IEnumerable<FunctionArgument> ExpectedArguments
+        {
+            get
+            {
+                yield break;
+            }
+
+        }
+
+        public FunctionValue ReturnValue
+        {
+            get
+            {
+                return FunctionValue.NONE;
+            }
+        }
+
+        public FunctionValue Execute(params FunctionArgument[] args)
+        {
+            Console.WriteLine(VersionCLI);
+            Console.WriteLine(VersionCSMIC);
+            Console.WriteLine(VersionStandardLibrary);
+
+            return FunctionValue.ZERO;
+        }
+
+        static string GetVersion(Assembly assembly)
+        {
+            var version = assembly.GetName()?.Version?.ToString()
+                ?? "Unknown";
+
+            return version;
+        }
+    }
+}

src/cs-mic-cli/Options.cs

@@ -6,6 +6,8 @@
 
         public bool Interactive { get; set; }
 
+        public bool Version { get; set; }
+
         public IEnumerable<string> Expression { get; set; } = Array.Empty<string>();
     }
 }

src/cs-mic-cli/Program.cs

@@ -18,6 +18,10 @@ namespace cs_mic_cli
             {
                 Description = "Starts an interactive session."
             };
+            var versionOption = new Option<bool>("--version", "-v")
+            {
+                Description = "Prints the version number of CS-MIC."
+            };
             var expressionArgument = new Argument<string[]>("expression")
             {
                 Arity = ArgumentArity.ZeroOrMore,
@@ -46,6 +50,7 @@ namespace cs_mic_cli
                 {
                     Verbose = parseResult.GetValue(verboseOption),
                     Interactive = parseResult.GetValue(interactiveOption),
+                    Version = parseResult.GetValue(versionOption),
                     Expression = parseResult.GetValue(expressionArgument) ?? Array.Empty<string>()
                 };
 
@@ -62,12 +67,20 @@ namespace cs_mic_cli
             
             Initializer.InitializeAll(inputInterpreter);
             inputInterpreter.RegisterFunction(new PrintVariables(inputInterpreter));
+            inputInterpreter.RegisterFunction(new Functions.Version());
 
             if(!options.Verbose)
             {
                 CSMic.Interpreter.Errors.errorStream = TextWriter.Null;
             }
 
+            if(options.Version)
+            {
+                Console.WriteLine(Functions.Version.VersionCLI);
+                Console.WriteLine(Functions.Version.VersionCSMIC);
+                Console.WriteLine(Functions.Version.VersionStandardLibrary);
+            }
+
             if (string.IsNullOrWhiteSpace(fullExpression) || options.Interactive)
             {
                 // console mode

src/cs-mic-cli/cs-mic-cli.csproj

@@ -8,6 +8,7 @@
 		<Nullable>enable</Nullable>
 		<PublishAot>true</PublishAot>
 		<InvariantGlobalization>true</InvariantGlobalization>
+		<Version>1.0.0</Version>
 	</PropertyGroup>
 
 	<ItemGroup>