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Improper Inheritance Lets say there are 2 classes class Foo and Bar. Foo has two features Do1 and Do2. Bar needs to use Do1 from Foo, but it doesn't need Do2 or needs feature that is equivalent to Do2 but does something completely different. Bad way: make Do2() on Foo virtual then override it in B...

One of Angular's strength's is client-side form validation. Dealing with traditional form inputs and having to use interrogative jQuery-style processing can be time-consuming and finicky. Angular allows you to produce professional interactive forms relatively easily. The ng-model directive provide...

The assignment operator = sets thr left hand operand's value to the value of right hand operand, and return that value: int a = 3; // assigns value 3 to variable a int b = a = 5; // first assigns value 5 to variable a, then does the same for variable b Console.WriteLine(a = 3 + 4); // prints ...

Sometimes you may need additional features from a directive. Instead of rewriting (copy) the directive, you can modify how the directive behaves. The decorator will be executed during $inject phase. To do so, provde a .config to your module. The directive is called myDirective, so you have to con...

Imagine that we have a class Math.php with logic of calculating of fiobanacci and factorial numbers. Something like this: <?php class Math { public function fibonacci($n) { if (is_int($n) && $n > 0) { $elements = array(); $elements[1] = 1; ...

install the required Microsoft.SqlServer.Types assembly; they are not installed by default, and are available from Microsoft here as "Microsoft® System CLR Types for Microsoft® SQL Server® 2012" - note that there are separate installers for x86 and x64. install Dapper.EntityFramew...

Basic usage If the value of the href-attribute begins with mailto: it will try to open an email client on click: <a href="mailto:[email protected]">Send email</a> This will put the email address [email protected] as the recipient for the newly created email. Cc and ...

<PropertyGroup> <!-- Definition of a Property named "TestCondition". A PropertyGroup may also be placed inside a Target. --> <TestCondition>True</TestCondition> </PropertyGroup> <!-- This Target will run after the "Clean" Target, su...

There is a constructor of the same name: DT <- data.table( x = letters[1:5], y = 1:5, z = (1:5) > 3 ) # x y z # 1: a 1 FALSE # 2: b 2 FALSE # 3: c 3 FALSE # 4: d 4 TRUE # 5: e 5 TRUE Unlike data.frame, data.table will not coerce strings to factors by default: sa...

For efficiency, data.table offers a way of altering a data.frame or list to make a data.table in-place: # example data.frame DF = data.frame(x = letters[1:5], y = 1:5, z = (1:5) > 3) # modification setDT(DF) Note that we do not <- assign the result, since the object DF has been modifi...

# example data DT1 = data.table(x = letters[1:2], y = 1:2, z = (1:2) > 3) Due to the way data.tables are manipulated, DT2 <- DT1 will not make a copy. That is, later modifications to the columns or other attributes of DT2 will affect DT1 as well. When you want a real copy, use DT2 = copy(...

Match (node_name:node_type {}), (node_name_two:node_type_two {}) CREATE (node_name)-[::edge_name{}]->(node_name_two)

Monotonic predicates can be debugged by applying declarative reasoning. In pure Prolog, a programming mistake can lead to one or all of the following phenomena: the predicate incorrectly succeeds in a case where it should fail the predicate incorrectly fails in a case where it should succeed t...

Examples of monotonic predicates are: unification with (=)/2 or unify_with_occurs_check/2 dif/2, expressing disequality of terms CLP(FD) constraints like (#=)/2 and (#>)/2, using a monotonic execution mode. Prolog predicates that only use monotonic goals are themselves monotonic. Monoton...

Here are examples of predicates that are not monotonic: meta-logical predicates like var/1, integer/1 etc. term comparison predicates like (@<)/2 and (@>=)/2 predicates that use !/0, (\+)/1 and other constructs that break monotonicity all-solutions predicates like findall/3 and setof/3. ...

Here are examples of how to use monotonic predicates instead of impure, non-monotonic constructs in your programs: dif/2 is meant to be used instead of non-monotonic constructs like (\=)/2 arithmetic constraints (CLP(FD), CLP(Q) and others) are meant to be used instead of moded arithmetic predi...

//Example 1 int[] array = { 1, 5, 2, 10, 7 }; // Select squares of all odd numbers in the array sorted in descending order IEnumerable<int> query = from x in array where x % 2 == 1 orderby x descending select x ...

To interact with WebElements in a webpage, first we need to identify the location of the element. By is the keyword available in selenium. You can locate the elements By.. By ID By Class Name By TagName By Name By Link Text By Partial Link Text By CSS Selector By XPath Using JavaScript ...

Option Compare Binary Binary comparison makes all checks for string equality within a module/class case sensitive. Technically, with this option, string comparisons are performed using sort order of the binary representations of each character. A < B < E < Z < a < b < e < z ...

The chan-signal crate provides a solution to handle OS signal using channels, altough this crate is experimental and should be used carefully. Example taken from BurntSushi/chan-signal. #[macro_use] extern crate chan; extern crate chan_signal; use chan_signal::Signal; fn main() { // S...