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pushd/popd (store current dir on stack and go to dest / pop prev dir and go to it)

$ pwd /home/bob/somedir1/somedir2/somedir3 $ pushd /home/bob/otherdir1/otherdir2 /home/bob/otherdir1/otherdir2 /home/bob/somedir1/somedir2/somedir3 $ popd /home/bob/somedir1/somedir2/somedir3 $ pushd /usr /usr /home/bob/somedir1/somedir2/somedir3 $ pushd /var /var /usr /home/bob/som...

Function compositions with multiple channels

Arrow is, vaguely speaking, the class of morphisms that compose like functions, with both serial composition and “parallel composition”. While it is most interesting as a generalisation of functions, the Arrow (->) instance itself is already quite useful. For instance, the following function: sp...

Using rewrite rules on overloaded functions

In this question, @Viclib asked about using rewrite rules to exploit typeclass laws to eliminate some overloaded function calls: Mind the following class: class ListIsomorphic l where toList :: l a -> [a] fromList :: [a] -> l a I also demand that toList . fromList == id. H...

Enumerating the Enumerable

The IEnumerable<T> interface is the base interface for all generic enumerators and is a quintessential part of understanding LINQ. At its core, it represents the sequence. This underlying interface is inherited by all of the generic collections, such as Collection<T>, Array, List<T&g...

In-line DIV using float

The div is a block-level element, i.e it occupies the whole of the page width and the siblings are place one below the other irrespective of their width. <div> <p>This is DIV 1</p> </div> <div> <p>This is DIV 2</p> </div> The output of...
CSS • Floats

Partially update the view

Makes an ajax request and updates only part of the view. Bean.java @ManagedBean @ViewScoped public class Bean { public Date getCurrentDate() { return new Date(); } } sample.xhtml <html xmlns="http://www.w3.org/1999/xhtml" xmlns:h="http://xmlns...

Send form parts and listen to the request

Makes a request only sending part of the form. The text1 value is set, but not text2, as the listener states. Bean.java @ManagedBean @ViewScoped public class Bean { private String text1; private String text2; public String getText1() { return text1; } pu...

Switch to a frame using C#

1. Switch to a frame by Index. Here we are switching to index 1. Index refers to the order of frames on the page. This should be used as a last resort, as frame id or names are much more reliable. driver.SwitchTo().Frame(1); 2. Switch to a frame by Name driver.SwitchTo().Frame("Name_Of_Fr...

Automatically processing data received from a serial port

Some devices connected through a serial port send data to your program at a constant rate (streaming data) or send data at unpredictable intervals. You can configure the serial port to execute a function automatically to handle data whenever it arrives. This is called the "callback function&quo...

Adding custom filters/functions

Here are some example on how to add new filters/functions to twig,the synax for adding Twig_Functions are the same as the Twig_Filter ones, just change the keywords accordingly <?php $twig = new Twig_Environment($loader); /* You can chain a global function */ $twig->addFilter(ne...

Making an outbound callout

This is an example on how to call a web service from salesforce. The code below is calling a REST based service hosted on data.gov to find farmers markets close to the zipcode. Please remember in order to invoke a HTTP callout from your org, you need to tweak the remote settings for the org. strin...

Creating & Managing Custom Settings

Creation To create a Custom Setting, go to: Classic Setup > Develop > Custom Settings > New Lightning Setup > Custom Code > Custom Settings > New Create your setting (see the Remarks later in this document for the differences between Hierarchy & List custom settings). You...

Using Hierarchy Custom Settings To Disable Workflow / Validation Rules

Custom Setting Custom Setting Field Custom Setting Field Value When the field is checked the validation rule will be disabled, for the running user or in this example, their profile - The rule can also be disabled for a whole Salesforce org - Validation Rule AND( /* the below is the...

Using Hierarchy Custom Settings To Disable Apex Code

Explanation In this example a simple Trigger has been created to change the Close Date of an Opportunity, that's about to be inserted or updated, to a date 10 days in the future. The Apex Controller custom setting's checkbox field enables the code to be disabled at the user / profile / org level. ...

Obtain an Instance of HTTP Request

To obtain an instance of an HTTP Request, class Illuminate\Http\Request need to be type hint either in the constructor or the method of the controller. Example code: <?php namespace App\Http\Controllers; /* Here how we illuminate the request class in controller */ use Illuminate\Http\Re...

Request Instance with other Parameters from routes in controller method

Sometimes we need to accept route params as well as access the HTTP Request params. We can still type hint the Requests class in laravel controller and achieve that as explained below E.g. We have a route that update a certain post like this (passing post id i route ) Route::put('post/{id}', 'Post...

Using a Semi-Join

Selecting all accounts that have open opportunity records under them SELECT Id, Name FROM Account WHERE AccountId IN (SELECT Id FROM Opportunity WHERE IsClosed = false)

Multi-line comments cannot be nested

In C, multi-line comments, /* and */, do not nest. If you annotate a block of code or function using this style of comment: /* * max(): Finds the largest integer in an array and returns it. * If the array length is less than 1, the result is undefined. * arr: The array of integers to search....

Using scoped services during application startup / Database Seeding

Resolving scoped services during application startup can be difficult, because there is no request and hence no scoped service. Resolving a scoped service during application startup via app.ApplicationServices.GetService<AppDbContext>() can cause issues, because it will be created in the sc...

Installation or Setup

Visual Studio 2013 can be downloaded here The setup is pretty easy.Select features you need and select the disk to install VS13 on.Click install and wait for it to finish.

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