SlowLangEngine is a C# library for easily creating simple programming languages. It was originally part of SlowLang but eventually became an indipendent project
- A simple lexer
- A very extensible parser
- Simple error handling
- A simple but extensible value system
- Create a new C# project.
- Import SlowLang.Engine from nuget
using your IDE or using the dotnet CLI like this:dotnet add package SlowLang.Engine - Copy this code into your Program.cs
using SlowLang.Engine;
using SlowLang.Engine.Statements;
using SlowLang.Engine.Tokens;
const string path = @"<YourSourceFile>";
string code = File.ReadAllText(path);
TokenList tokenList = Lexer.Lex(code);
Statement[] statements = Statement.ParseMultiple(tokenList);
//This is an extension method on IEnumerable<Statement>
//that will execute all Statements in the list.
statements.Execute();This will lex, parse and execute your code
- Now you can create your own Statements like this:
public class MyStatement : Statement, IInitializable
{
private string keyword;
//This static method will automatically get called on all classes that implement IInitializable
public static void Initialize()
{
//Here, you can register you Statement so you don't have to do that at a central location
StatementRegistration.Create<MyStatement>(
//This is a sequence of Tokens that need to be matched in order to start the parsing process.
TokenType.Keyword,
TokenType.OpeningBrace,
TokenType.ClosingBrace,
TokenType.Semicolon
)
.Register();
}
protected override void OnParse(ref TokenList list)
{
//On parse gets called as soon as the parsing process begins
keyword = list.Peek().RawContent; // Get the keyword from the Tokenlist and store its value
//The parser will automatically remove the rest of the Statements tokens from the TokenList
}
public override Value Execute()
{
//This method gets called every time this Statement gets executed
Console.WriteLine($"Function {keyword} was called");
//Return the return value of the Statement
//Since this Statement doesn't have a return value, just return SlowVoid.I (NOT NULL!)
return SlowVoid.I;
}
}- Create your source code file and save for example
hello();
This should now write "Function hello was called" to the console