Tutorial by Examples: n

CSS enclosed in <style></style> tags within an HTML document functions like an external stylesheet, except that it lives in the HTML document it styles instead of in a separate file, and therefore can only be applied to the document in which it lives. Note that this element must be insid...

Use inline styles to apply styling to a specific element. Note that this is not optimal. Placing style rules in a <style> tag or external CSS file is encouraged in order to maintain a distinction between content and presentation. Inline styles override any CSS in a <style> tag or extern...

To check the equality of Date values: var date1 = new Date(); var date2 = new Date(date1.valueOf() + 10); console.log(date1.valueOf() === date2.valueOf()); Sample output: false Note that you must use valueOf() or getTime() to compare the values of Date objects because the equality operato...

Using the Cars Table, we will calculate the total, max, min and average amount of money each costumer spent and haw many times (COUNT) she brought a car for repairing. Id CustomerId MechanicId Model Status Total Cost SELECT CustomerId, SUM(TotalCost) OVER(PARTITION BY Cust...

When the Repeater is Bound, for each item in the data, a new table row will be added. <asp:Repeater ID="repeaterID" runat="server" OnItemDataBound="repeaterID_ItemDataBound"> <HeaderTemplate> <table> <thead> ...

Rebasing reapplies a series of commits on top of another commit. To rebase a branch, checkout the branch and then rebase it on top of another branch. git checkout topic git rebase master # rebase current branch onto master branch This would cause: A---B---C topic / D---E---F---G...

ALTER TABLE Employees ADD StartingDate date NOT NULL DEFAULT GetDate(), DateOfBirth date NULL The above statement would add columns named StartingDate which cannot be NULL with default value as current date and DateOfBirth which can be NULL in Employees table.

from itertools import imap from future_builtins import map as fmap # Different name to highlight differences image = [[1, 2, 3], [4, 5, 6], [7, 8, 9]] list(map(None, *image)) # Out: [(1, 4, 7), (2, 5, 8), (3, 6, 9)] list(fmap(None, *image)) # Out: [(1, 4, 7), (2, 5, 8),...

The system header TargetConditionals.h defines several macros which you can use from C and Objective-C to determine which platform you're using. #import <TargetConditionals.h> // imported automatically with Foundation - (void)doSomethingPlatformSpecific { #if TARGET_OS_IOS // code t...

Abbreviated from https://blogs.dropbox.com/developers/2013/07/using-oauth-2-0-with-the-core-api/: Step 1: Begin authorization Send the user to this web page, with your values filled in: https://www.dropbox.com/oauth2/authorize?client_id=<app key>&response_type=code&redirect_uri=<...

R has several built-in functions that can be used to print or display information, but print and cat are the most basic. As R is an interpreted language, you can try these out directly in the R console: print("Hello World") #[1] "Hello World" cat("Hello World\n") #H...

To have Git ignore certain files across all repositories you can create a global .gitignore with the following command in your terminal or command prompt: $ git config --global core.excludesfile <Path_To_Global_gitignore_file> Git will now use this in addition to each repository's own .git...

A submodule is always checked out at a specific commit SHA1 (the "gitlink", special entry in the index of the parent repo) But one can request to update that submodule to the latest commit of a branch of the submodule remote repo. Rather than going in each submodule, doing a git checkout...

If your latest commit is not published yet (not pushed to an upstream repository) then you can amend your commit. git commit --amend This will put the currently staged changes onto the previous commit. Note: This can also be used to edit an incorrect commit message. It will bring up the default...

The trap is reset for subshells, so the sleep will still act on the SIGINT signal sent by ^C (usually by quitting), but the parent process (i.e. the shell script) won't. #!/bin/sh # Run a command on signal 2 (SIGINT, which is what ^C sends) sigint() { echo "Killed subshell!" } ...

You can use the trap command to "trap" signals; this is the shell equivalent of the signal() or sigaction() call in C and most other programming languages to catch signals. One of the most common uses of trap is to clean up temporary files on both an expected and unexpected exit. Unfortu...

This is an example of dereferencing a NULL pointer, causing undefined behavior. int * pointer = NULL; int value = *pointer; /* Dereferencing happens here */ A NULL pointer is guaranteed by the C standard to compare unequal to any pointer to a valid object, and dereferencing it invokes undefined...

int i = 42; i = i++; /* Assignment changes variable, post-increment as well */ int a = i++ + i--; Code like this often leads to speculations about the "resulting value" of i. Rather than specifying an outcome, however, the C standards specify that evaluating such an expression produc...

int foo(void) { /* do stuff */ /* no return here */ } int main(void) { /* Trying to use the (not) returned value causes UB */ int value = foo(); return 0; } When a function is declared to return a value then it has to do so on every possible code path through it. Undefined beh...

alias word='command' Invoking word will run command. Any arguments supplied to the alias are simply appended to the target of the alias: alias myAlias='some command --with --options' myAlias foo bar baz The shell will then execute: some command --with --options foo bar baz To include mul...