Added Unary operators and parenthetical precedence

Author: Samathingamajig

BarkScript.cpp

@@ -4,7 +4,7 @@
 #include "lexer.h"
 #include "parser.h"
 
-const std::string bsversion = "0.0.5.1";
+const std::string bsversion = "0.0.6";
 
 int main() {
     std::cout << "BarkScript version " << bsversion << std::endl;

Parser.cpp

@@ -31,6 +31,20 @@ ParseResult Parser::factor() {
     if (token.type == tokens::NUMBER) {
         nextToken();
         return pr.success(makeSharedNode(NumberNode(token)));
+    } else if (in_array(token.type, { tokens::PLUS, tokens::MINUS })) {
+        nextToken();
+        spNode factorRes = pr.registerPR(factor());
+        if (pr.hasError()) return pr;
+        return pr.success(makeSharedNode(UnaryOperatorNode(token, factorRes)));
+    } else if (token.type == tokens::OPEN_PAREN) {
+        nextToken();
+        spNode exprRes = pr.registerPR(expr());
+        if (pr.hasError()) return pr;
+        if (currentToken.type == tokens::CLOSE_PAREN) {
+            nextToken();
+            return pr.success(exprRes);
+        }
+        return pr.failure(makeSharedError(InvalidSyntaxError(currentToken.positionStart, currentToken.positionEnd, "Expected a ')'")));
     } else {
         pr.registerPR(makeSharedNode(ErrorNode(token)));
         return pr.failure(makeSharedError(InvalidSyntaxError(token.positionStart, token.positionEnd, "Expected a number")));

ast.h

@@ -62,6 +62,18 @@ struct BinaryOperatorNode : Node {
     }
 };
 
+struct UnaryOperatorNode : Node {
+    UnaryOperatorNode(Token token, spNode rightNode) {
+        this->nodeType = "UNOP";
+        this->token = token;
+        this->rightNode = rightNode;
+    }
+
+    std::string to_string() override {
+        return "(" + token.value + ", " + rightNode->to_string() + ")";
+    }
+};
+
 struct ErrorNode : Node {
     ErrorNode(Token token) {
         this->nodeType = "ERROR";

syntax.txt

@@ -3,5 +3,5 @@ expr     : term ((PLUS|MINUS) term)*
 term     : factor ((ASTERISK|F_SLASH) factor)*
 
 factor   : NUMBER
-
-
+         : (PLUS|MINUS) factor
+         : OPEN_PAREN expr CLOSE_PAREN