• 🤖 No AI was used in the creation of this, all my own hard work.
• This is my first project using C# and I made it to learn how C# works
• This is not a throwaway project, I hope to develop it more and refactor in the future

Verity

Verity is a toy number "language" that I hope to develop and improve more in the future when I get more skills into either a DSL or a fully fleshed out programming language.

How it works (currently)

As of right now Verity is a REPL which allows you to input DMAS, BI still needs to be implemented.

REPL -> Lexer -> Parser -> Evaluator

1 + 1 == 2
1 + 2 * 3 == 7

• Unit Testing
• Lexer
• Parser
• Evaluator
• Division, Multiplication, Addition, Subtraction
• REPL
• Brackets () ---> (3 * 2 + 4) * 4 = 40
• Indices ^2 ---> 2+2*3^2 = 2 + (2 * 3 ^ 2) = 20

In the future, I plan to get Verity to a working state which allows something simple like;

let x = 69
let y = 420
let z = x + y * (x - y ^ 2)
writeln z

Lexer

Located here Every input is ran through the lexer to begin with where it returns data i.e. Tokens;

Tokens: List<Token>

This can then be used by the Parser (see below)

Parser

Located here

The parser first tries to ParseExpression() which first requires ParseTerm() which first requires ParseFactor(), allowing for the proper order of DMAS to take place and it outputs a ParserResult which has a ASTNode which can be passed to the Evaluator

Evaluator

Located here

Goes through the ASTNode provided recursively looking for a NumberExpression which then returns the expression.Value, if it is instead given a BinaryExpression it will calculate both the left and right and use the SyntaxKind i.e. SyntaxKind.Star and realise that it needs to multiply. After all recursion is done, it returns a single float value of the evaluated expression.

Unit Testing

Located here

Unit Testing was done via Xunit, it's quite simple and only has one test at the moment which expects all the expression related features to successfully work.