{"id":697,"date":"2018-11-22T04:01:28","date_gmt":"2018-11-22T04:01:28","guid":{"rendered":"http:\/\/www.onux.com\/jspp\/blog\/?p=697"},"modified":"2018-11-22T04:01:28","modified_gmt":"2018-11-22T04:01:28","slug":"tips-tricks-overriding-tostring","status":"publish","type":"post","link":"https:\/\/www.onux.com\/jspp\/blog\/tips-tricks-overriding-tostring\/","title":{"rendered":"Tips & Tricks: Overriding ‘toString’"},"content":{"rendered":"

JS++ has a default ‘toString’ method implementation but, sometimes, it is necessary to override this implementation. For example, when using Console.log<\/code><\/a>, it may be desirable to be able to fully log and inspect a complex JS++ object.<\/p>\n

In addition to the Unified External Type<\/a>, there is also a “Unified Internal Type”: System.Object<\/a>. All JS++ classes, including user-defined classes, inherit from System.Object. Due to auto-boxing, even primitive types such as int<\/code> (wrapped by System.Integer32<\/code>), inherit from System.Object<\/code>.<\/p>\n

Aside: Don’t worry about the performance implications of auto-boxing. JS++ is able to optimize auto-boxing to the point that toString<\/code> is actually 7.2% faster in JS++ than JavaScript in the worst case (assuming the JavaScript variable is monomorphically-typed) and more than 50% faster for polymorphically-typed (and potentially type-unsafe) JavaScript variables as shown in benchmarks here<\/a>.<\/p><\/blockquote>\n

System.Object has a toString method<\/a> which is marked as virtual<\/code>. In other words, this method can be overridden by derived classes – which are effectively all classes in JS++. Here’s an example of how to do it:<\/p>\n

\r\nimport System;\r\n\r\nclass Point\r\n{\r\n    int x;\r\n    int y;\r\n\r\n    Point(int x, int y) {\r\n        this.x = x;\r\n        this.y = y;\r\n    }\r\n\r\n    override string toString() {\r\n        return \"(\" + x.toString() + \", \" + y.toString() + \")\";\r\n    }\r\n}\r\n\r\nPoint p = new Point(1,2);\r\nConsole.log(p); \/\/ \"(1, 2)\"\r\n<\/pre>\n
You’ll notice the Console.log<\/code> statement doesn’t even make an explicit toString<\/code> call. The reason is because passing any JS++ object to Console.log<\/code> will call the toString<\/code> method on the object for you.<\/p>\n","protected":false},"excerpt":{"rendered":"
JS++ has a default ‘toString’ method implementation but, sometimes, it is necessary to override this implementation. For example, when using Console.log, it may be desirable to be able to fully log and inspect a complex JS++ object. In addition to the Unified External Type, there is also a “Unified Internal Type”: System.Object. All JS++ classes, … Continue reading “Tips & Tricks: Overriding ‘toString’”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[2,18],"tags":[],"_links":{"self":[{"href":"https:\/\/www.onux.com\/jspp\/blog\/wp-json\/wp\/v2\/posts\/697"}],"collection":[{"href":"https:\/\/www.onux.com\/jspp\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.onux.com\/jspp\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.onux.com\/jspp\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.onux.com\/jspp\/blog\/wp-json\/wp\/v2\/comments?post=697"}],"version-history":[{"count":6,"href":"https:\/\/www.onux.com\/jspp\/blog\/wp-json\/wp\/v2\/posts\/697\/revisions"}],"predecessor-version":[{"id":765,"href":"https:\/\/www.onux.com\/jspp\/blog\/wp-json\/wp\/v2\/posts\/697\/revisions\/765"}],"wp:attachment":[{"href":"https:\/\/www.onux.com\/jspp\/blog\/wp-json\/wp\/v2\/media?parent=697"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.onux.com\/jspp\/blog\/wp-json\/wp\/v2\/categories?post=697"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.onux.com\/jspp\/blog\/wp-json\/wp\/v2\/tags?post=697"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}