Tutorial by Examples: me

The -CaseSensitive parameter enforces switch statements to perform exact, case-sensitive matching against conditions. Example: switch -CaseSensitive ('Condition') { 'condition' {'First Action'} 'Condition' {'Second Action'} 'conditioN' {'Third Action'} } Output: Second Act...

The -file parameter allows the switch statement to receive input from a file. Each line of the file is evaluated by the switch statement. Example file input.txt: condition test Example switch statement: switch -file input.txt { 'condition' {'First Action'} 'test' {'Second Action...

Compile errors can be generated using the preprocessor. This is useful for a number of reasons some of which include, notifying a user if they are on an unsupported platform or an unsupported compiler. e.g. Return Error if gcc version is 3.0.0 or earlier. #if __GNUC__ < 3 #error "This cod...

It is common for memory performance to compress multiple values into a single primitive value. This may be useful to pass various information into a single variable. For example, one can pack 3 bytes - such as color code in RGB - into an single int. Packing the values // Raw bytes as input byte...

When NSLog is asked to print empty string, it omits the log completely. NSString *name = @""; NSLog(@"%@", name); // Resolves to @"" The above code will print nothing. It is a good practice to prefix logs with labels: NSString *name = @""; NSLog(@&quo...

The Objective-C runtime allows you to change the implementation of a method at runtime. This is called method swizzling and is often used to exchange the implementations of two methods. For example, if the methods foo and bar are exchanged, sending the message foo will now execute the implementation...

Variables hold data. Name them after what they're used for, not after their data type or scope, using a noun. If you feel compelled to number your variables (e.g. thing1, thing2, thing3), then consider using an appropriate data structure instead (e.g. an array, a Collection, or a Dictionary). Names...

Procedures do something. Name them after what they're doing, using a verb. If accurately naming a procedure is not possible, likely the procedure is doing too many things and needs to be broken down into smaller, more specialized procedures. Some common VBA naming conventions go thus: For all Pr...

You can use the Enumerable class alongside Linq queries to convert for loops into Linq one liners. Select Example Opposed to doing this: var asciiCharacters = new List<char>(); for (var x = 0; x < 256; x++) { asciiCharacters.Add((char)x); } You can do this: var asciiCharacter...

To select the children of an element you can use the children() method. <div class="parent"> <h2>A headline</h2> <p>Lorem ipsum dolor sit amet...</p> <p>Praesent quis dolor turpis...</p> </div> Change the color of all the ...

git shortlog summarizes git log and groups by author If no parameters are given, a list of all commits made per committer will be shown in chronological order. $ git shortlog Committer 1 (<number_of_commits>): Commit Message 1 Commit Message 2 ... Committer 2 (<number_of_...

When assigning named methods to delegates, they will refer to the same underlying object if: They are the same instance method, on the same instance of a class They are the same static method on a class public class Greeter { public void WriteInstance() { Console.Write...

Named methods can be assigned to delegates with matching signatures: public static class Example { public static int AddOne(int input) { return input + 1; } } Func<int,int> addOne = Example.AddOne Example.AddOne takes an int and returns an int, its signature ...

In Python 2, exec is a statement, with special syntax: exec code [in globals[, locals]]. In Python 3 exec is now a function: exec(code, [, globals[, locals]]), and the Python 2 syntax will raise a SyntaxError. As print was changed from statement into a function, a __future__ import was also added. ...

The dynamics of the Geometric Brownian Motion (GBM) are described by the following stochastic differential equation (SDE): I can use the exact solution to the SDE to generate paths that follow a GBM. Given daily parameters for a year-long simulation mu = 0.08/250; sigma = 0.25/sqrt(...

Template may accept both lvalue and rvalue references using forwarding reference: template <typename T> void f(T &&t); In this case, the real type of t will be deduced depending on the context: struct X { }; X x; f(x); // calls f<X&>(x) f(X()); // calls f<X>(...

<?php for ($i = 0; $i < 10; $i++): do_something($i); endfor; ?> <?php for ($i = 0; $i < 10; $i++): ?> <p>Do something in HTML with <?php echo $i; ?></p> <?php endfor; ?>

<?php while ($condition): do_something(); endwhile; ?> <?php while ($condition): ?> <p>Do something in HTML</p> <?php endwhile; ?>

<?php foreach ($collection as $item): do_something($item); endforeach; ?> <?php foreach ($collection as $item): ?> <p>Do something in HTML with <?php echo $item; ?></p> <?php endforeach; ?>

<?php switch ($condition): case $value: do_something(); break; default: do_something_else(); break; endswitch; ?> <?php switch ($condition): ?> <?php case $value: /* having whitespace before your cases will cause an error */ ?&g...