In Golang, nil is a predefined identifier that carries different meanings in various contexts, but typically represents "none", "empty" or "zero value". It can be assigned to variables of pointer, slice, map, channel, function, and interface types. Understanding the significance of nil is crucial for writing robust Go programs, as mishandling nil can lead to unexpected issues.nil in PointersIn Go, pointers are a fundamental type that stores the memory address of a variable. When a pointer is declared but not initialized, its value is nil. The following example code illustrates this:package mai...

With the evolvement of JavaScript, lots of new features have been added this old but robust language.  Among them are lots of functional programming language related functions like map, filter, each etc. In this post, we will cover one function map and its interesting behavior.Before dive into the details, let first take an example, do you know the output of below function call?['1', '7', '11'].map(parseInt)You may think that it's easy and the output would be[1, 7, 11]Can you try to run this by yourself and you may be surprised of the output. The actual result is[1, NaN, 3]What's happenin...

OpenLDAP proxy is used to proxy ldap request and response between clients and servers, different servers may have different representations/attributes to mean the same thing. For example, in one LDAP server, the firstName may be represented by firstName, it may be represented by givenName in a different server. However, from the client perspective, it only wants to get the firstName, it doesn't care about the backend attributes.In this case, attribute mapping can help provide a virtual view of the backend data. In another post OpenLDAP Proxy -- Tricks and tips, we have introduced how attribute...

Recently, the new release of Apple map is criticized by many users because of its search results accuracy. By this time, Nokia which has its map service Ovi Maps has a comparison of three maps in its Conversations blog. These three maps are the one on the Lumia 920, the Google Map on Samsung Galaxy S3, the map on Apple iPhone 5, It wants to show that Nokia is the best among them. Let's take a look:1. Offline modeOn Lumia 920 Map, the map of the entire country is downloaded, you can position, search, and route offline. Galaxy S3 will only be able to download a map of the city information offlin...

Apple released many new products and new software in this year's WWDC.They include the new MacBook Air, the new MacBook Pro, iOS6 and more. Among them, the Apple's new map app may get the attention of people who love or hate Google. In iOS6, Apple ruled out Google map, they are saying goodbye to Google. This new Map app integrated with Siri will have voice navigation feature. This means people can receive real time traffic update and the map can offer alternate routes. Also, it will be a 3D map having a feature Flyover which will provide interactive 3D views. These 3D images have been taken th...