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Paramorphisms model primitive recursion. At each iteration of the fold, the folding function receives the subtree for further processing. para :: Functor f => (f (Fix f, a) -> a) -> Fix f -> a para f = f . fmap (\x -> (x, para f x)) . unFix The Prelude's tails can be modelled as ...

Apomorphisms model primitive corecursion. At each iteration of the unfold, the unfolding function may return either a new seed or a whole subtree. apo :: Functor f => (a -> f (Either (Fix f) a)) -> a -> Fix f apo f = Fix . fmap (either id (apo f)) . f Note that apo and para are dual...

First, Install Java SE Development Kit This can be as simple as downloading, double-clicking on the downloaded file, and following the installation instructions. For install Java SE Development Kit download it from official web site. Java SE Development Kit. Downloads After JDK install is complete...

Nobody wants to require or include every time a class or inheritance is used. Because it can be painful and is easy to forget, PHP is offering so called autoloading. If you are already using Composer, read about autoloading using Composer. What exactly is autoloading? The name basically says it al...

Only the homepage works, all other pages return 404 Make sure mod_rewrite module has been installed in Apache and been enabled to load. See step 2 for info on how to do this here: https://www.digitalocean.com/community/tutorials/how-to-set-up-mod_rewrite-for-apache-on-ubuntu-14-04 Make sure the y...

Mage::getBaseUrl(Mage_Core_Model_Store::URL_TYPE_WEB);

Profiling string concatanation: In [1]: import string In [2]: %%timeit s=""; long_list=list(string.ascii_letters)*50 ....: for substring in long_list: ....: s+=substring ....: 1000 loops, best of 3: 570 us per loop In [3]: %%timeit long_list=list(string.ascii_letters)*50...

Profiling repetition of elements in an array >>> import timeit >>> timeit.timeit('list(itertools.repeat("a", 100))', 'import itertools', number = 10000000) 10.997665435877963 >>> timeit.timeit('["a"]*100', number = 10000000) 7.118789926862576

Profiling concatanation of numbers python -m timeit "'-'.join(str(n) for n in range(100))" 10000 loops, best of 3: 29.2 usec per loop python -m timeit "'-'.join(map(str,range(100)))" 100000 loops, best of 3: 19.4 usec per loop

The source code with @profile directive before the function we want to profile: import requests @profile def slow_func(): s = requests.session() html=s.get("https://en.wikipedia.org/").text sum([pow(ord(x),3.1) for x in list(html)]) for i in range(50): s...

Editing the width of Separator Lines You can set make your table view's separator lines extend the to various widths across the table by changing the layoutMargins: property on your cell(s). This can be achieved in a number of ways. Changing the Separator Lines for specific cells In either your t...

Description An image maps is an image with clickable areas that usually act as hyperlinks. The image is defined by the <img> tag, and the map is defined by a <map> tag with <area> tags to denote each clickable area. Use the usemap and name attributes to bind the image and the map...

Copying a partial array with the static Array.Copy() method, beginning at index 0 in both, source and destination: var sourceArray = new int[] { 11, 12, 3, 5, 2, 9, 28, 17 }; var destinationArray= new int[3]; Array.Copy(sourceArray, destinationArray, 3); // destinationArray will have 11,12 and...

This code is to add and remove a value from a flagged enum-instance: [Flags] public enum MyEnum { Flag1 = 1 << 0, Flag2 = 1 << 1, Flag3 = 1 << 2 } var value = MyEnum.Flag1; // set additional value value |= MyEnum.Flag2; //value is now Flag1, Flag2 value...

Sometimes we need to make a lot of POST requests to one or many different endpoints. To deal with this scenario, we can use multi_curl. First of all, we create how many requests as needed exactly in the same way of the simple example and put them in an array. We use the curl_multi_init and add eac...

Elm Reactor is the essential tool for prototyping your application. Please note, that you will not be able to compile Main.elm with Elm Reactor, if you are using Http.App.programWithFlags or Ports Running elm-reactor in a projects directory will start a web server with a project explorer, that all...

To create a XML using DOMDocument,basically, we need to create all the tags and attributes using the createElement() and createAttribute() methods and them create the XML structure with the appendChild(). The example below includes tags, attributes, a CDATA section and a different namespace for the...

Following the 'Form Request Validation' example, the same Request Class can be used for POST, PUT, PATCH so you do not have to create another class using the same/similar validations. This comes in handy if you have attributes in your table that are unique. /** * Get the validation rules that a...

Just like most other C-style languages, each statement is terminated with a semicolon. Also, a closing tag is used to terminate the last line of code of the PHP block. If the last line of PHP code ends with a semicolon, the closing tag is optional if there is no code following that final line of co...

Anonymous classes were introduced into PHP 7 to enable for quick one-off objects to be easily created. They can take constructor arguments, extend other classes, implement interfaces, and use traits just like normal classes can. In its most basic form, an anonymous class looks like the following: ...