fn parseSingleAssignExpr(p: *Parse) !?Node.Index
fn parseSingleAssignExpr(p: *Parse) !?Node.Index { const lhs = try p.parseExpr() orelse return null; const tag = assignOpNode(p.tokenTag(p.tok_i)) orelse return lhs; return try p.addNode(.{ .tag = tag, .main_token = p.nextToken(), .data = .{ .node_and_node = .{ lhs, try p.expectExpr(), } }, }); }