Tutorial by Examples: bug

Debugging with IEx.pry/0 is quite simple. require IEx in your module Find the line of code you want to inspect Add IEx.pry after the line Now start your project (e.g. iex -S mix). When the line with IEx.pry/0 is reached the program will stop and you have the chance to inspect. It is like a ...
Writes an error message to the console if the assertion is false. Otherwise, if the assertion is true, this does nothing. console.assert('one' === 1); Multiple arguments can be provided after the assertion–these can be strings or other objects–that will only be printed if the assertion is fals...
By default, most of the information is hidden from the user. You can use -v switches to get a verbose log of the connection attempt, which will usually pinpoint the problem by showing why the behavior is different than you expect. Let's assume you are connecting to the server example.com using ssh ...
At run time the following would display a list of url in your console and continue computation payload = [{url:..., title:...}, {url=..., title=...}] main = payload |> List.map .url -- only takes the url |> Debug.log " My list of URLs" -- pass the url...
Docker is just a fancy way to run a process, not a virtual machine. Therefore, debugging a process "in a container" is also possible "on the host" by simply examining the running container process as a user with the appropriate permissions to inspect those processes on the host (...
Both Chrome and Safari have built in debuggers. With Chrome, all you have to do is right-click on a web page and 'Inspect Element'. With Safari, you'll have to go into Preferences > Advanced and click on 'Show Develop menu in menu bar'. With Firefox, you'll need to install Firebug
You'll need to add debugger statements to your code: Meteor.methods({ doSomethingUself: function(){ debugger; niftyFunction(); } });
For server side debugging, you'll need to use a tool like Node Inspector. Before you get started, check out some of these useful tutorials. HowToNode - Debugging with Node Inspector Strongloop - Debugging Applications Easily Debugging Meteor.js Walkthrough with Screenshots of Using Node Inspecto...
Besides Node Inspector, some people have reported success with a npm utility called debug. MeteorHacks - Debugging Meteor with npm debug
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The following are the steps to start an Eclipse remote debugger. This is useful when the application is not started from a server instance within Eclipse. This feature is really powerful and can also help debugging code which resides in the test or production environment. Let's have a look at the se...
Use "-x" to enable debug output of executed lines. It can be run on an entire session or script, or enabled programmatically within a script. Run a script with debug output enabled: $ bash -x myscript.sh Or $ bash --debug myscript.sh Turn on debugging within a bash script. It may ...
An extension to PHP called Xdebug is available to assist in profiling PHP applications, as well as runtime debugging. When running the profiler, the output is written to a file in a binary format called "cachegrind". Applications are available on each platform to analyze these files. To...
The current frame rate (in FPS, Frames Per Second) and total number of SKNodes in the scene (nodeCount, each sprite is an SKNode but other objects in the scene are also SKNodes) can be shown in the bottom right hand corner of the view. These can be useful when turned on (set to true) for debugging ...
0.170.18.0 At the time of writing (July 2016) elm-reactor has been temporarily stripped of its time traveling functionality. It's possible to get it, though, using the jinjor/elm-time-travel package. It's usage mirrors Html.App or Navigation modules' program* functions, for example instead of: im...
Xdebug is a PHP extension which provides debugging and profiling capabilities. It uses the DBGp debugging protocol. There are some nice features in this tool: stack traces on errors maximum nesting level protection and time tracking helpful replacement of standard var_dump() function for displ...
To be able to debug an application is very important to understand the flow of an application's logic and data. It helps solving logical bugs and adds value to the programming experience and code quality. Two popular gems for debugging are debugger (for ruby 1.9.2 and 1.9.3) and byebug (for ruby &g...
Debug Print shows the instance representation that is most suitable for debugging. print("Hello") debugPrint("Hello") let dict = ["foo": 1, "bar": 2] print(dict) debugPrint(dict) Yields >>> Hello >>> "Hello" >&gt...
A Cordova application runs as a website on a WebView component within the native mobile platform. Debugging a cordova application can therefore be done by utilizing your favourite browsers development tools. The following steps are needed to hook the application, running on the device, to the Chrome...
Let's say your launch activity is called MainActivity, in your app com.example.myapp. In the manifest: <activity android:name=".MainActivity" > <intent-filter> <action android:name="android.intent.action.MAIN"/> ...

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