Allow for short variable assignment

src/lang/Nub.Lang/Frontend/Parsing/Parser.cs

@@ -216,6 +216,17 @@ public class Parser
     private StatementNode ParseStatementIdentifier(int startIndex, IdentifierToken identifier)
     {
         var symbol = ExpectSymbol();
+
+        if (TryGetBinaryOperator(symbol.Symbol, out var binaryOperator) && Peek().TryGetValue(out var next) && next is SymbolToken { Symbol: Symbol.Assign })
+        {
+            Next();
+            var left = new IdentifierNode(GetTokensForNode(startIndex), identifier.Value);
+            var right = ParseExpression();
+            var binOp = new BinaryExpressionNode(GetTokensForNode(startIndex), left, binaryOperator.Value, right);
+
+            return new VariableAssignmentNode(GetTokensForNode(startIndex), identifier.Value, binOp);
+        }
+
         switch (symbol.Symbol)
         {
             case Symbol.DoubleColon:
@@ -286,7 +297,7 @@ public class Parser
         {
             value = ParseExpression();
         }
-        
+
         return new VariableDeclarationNode(GetTokensForNode(startIndex), name, type, value);
     }
 
@@ -643,6 +654,7 @@ public class Parser
                 {
                     @namespace = ExpectIdentifier().Value;
                 }
+
                 return new NubStructType(@namespace, name);
             }
         }