Tutorial by Examples: ed

Responding to a conditional request for cached content

Send a 304 Not Modified response status from the server send in response to a client request that contains headers If-Modified-Since and If-None-Match, if the request resource hasn’t changed. For example if a client request for a web page includes the header If-Modified-Since: Fri, 22 Jul 2016 14:3...

HTTP • HTTP Status Codes

Actions and semantic predicates

A lexer action is a block of arbitrary code in the target language surrounded by {...}, which is executed during matching: IDENTIFIER: [A-Z]+ { log("matched rule"); }; A semantic predicate is a block of arbitrary code in the target language surrounded by {...}?, which evaluates to a bo...

ANTLR • Lexer rules in v4

Calling other seeders

Within your DatabaseSeeder class you are able to call other seeders $this->call(TestSeeder::class) This allows you to keep one file where you can easily find your seeders. Keep in mind that you need to pay attention to the order of your calls regarding foreign key constraints. You can't refe...

Laravel • Seeding

Wait for DOM to be loaded

Use DOMContentLoaded when the <script> code interacting with DOM is included in the <head> section. If not wrapped inside the DOMContentLoaded callback, the code will throw errors like Cannot read something of null document.addEventListener('DOMContentLoaded', function(event) { ...

DOM • Getting started with DOM

Import function from unmanaged C++ DLL

Here is an example of how to import a function that is defined in an unmanaged C++ DLL. In the C++ source code for "myDLL.dll", the function add is defined: extern "C" __declspec(dllexport) int __stdcall add(int a, int b) { return a + b; } Then it can be included into ...

C# Language • Interoperability

XOR Linked List

A XOR Linked list is also called a Memory-Efficient Linked List. It is another form of a doubly linked list. This is highly dependent on the XOR logic gate and its properties. Why is this called the Memory-Efficient Linked List? This is called so because this uses less memory than a traditional d...

data-structures • Linked List

Module dependencies

In a multi-project gradle build, you can have a dependency with another module in your build. Example: dependencies { // Dependency on the "mylibrary" module from this project compile project(":mylibrary") } The compile project(':mylibrary') line decla...

android-gradle • Declare Dependencies

Generalized Booleans

Actually any value different from NIL is considered a true value in Common Lisp. For instance: CL-USER> (let ((a (+ 2 2))) (if a a "Oh my! 2 + 2 is equal to NIL!")) 4 This fact can be combined with the boolean operators to make programs m...

common-lisp • Booleans and Generalized Booleans

Editing and Viewing Batch Files

Any ASCII editor can edit batch files. A list of editors that can syntax highlight batch syntax can be found here. You can also use the default notepad shipped with windows to edit and view a batch file, although it does not offer syntax highlighting. To open notepad: Press Win 𐌎+R, type notepa...

batch-file • Getting started with batch-file

Selecting a certain line from a list based on a word in certain location

I have the following list: 1. Alon Cohen 2. Elad Yaron 3. Yaron Amrani 4. Yogev Yaron I want to select the first name of the guys with the Yaron surname. Since I don't care about what number it is I'll just put it as whatever digit it is and a matching dot and space after it from the beginni...

Regular Expressions • Matching Simple Patterns

Cache personalized response for 1 minute

Cache-Control: private, max-age=60 private specifies that the response can be cached only for user who requested the resource, and can't be reused when other users request the same resource. This is appropriate for responses that depend on cookies.

HTTP • Caching HTTP responses

Stop use of cached resources without checking with the server first

Cache-Control: no-cache The client will behave as if the response was not cached. This is appropriate for resources that can unpredictably change at any time, and which users must always see in the latest version. Responses with no-cache will be slower (high latency) due to need to contact the s...

HTTP • Caching HTTP responses

Request responses not to be stored at all

Cache-control: no-store Instructs clients no to cache the response in any way, and to forget it at soon as possible. This directive was originally designed for sensitive data (today HTTPS should be used instead), but can be used to avoid polluting caches with responses that can't be reused. It...

HTTP • Caching HTTP responses

Obsolete, redundant and non-standard headers

Expires — specifies date when the resource becomes stale. It relies on servers and clients having accurate clocks and supporting time zones correctly. Cache-control: max-age takes precedence over Expires, and is generally more reliable. post-check and pre-check directives are non-standard I...

HTTP • Caching HTTP responses

Interactive and screen-based commands

Many commands and programs in the remote side are screen-based (e.g. mc) or they need to ask password (e.g. sudo), to be able to run these kind of programs you can use option -t. ssh -t [email protected] sudo ls / [sudo] password for alice: bin root dev etc home lib mnt opt proc root run usr ...

Secure Shell • Remote commands

Simple remote deploy fabfile.py

Fabric is a Python (2.5-2.7) library and command-line tool for streamlining the use of SSH for application deployment or systems administration tasks. It lets you execute arbitrary Python functions via the command line. Install fabric via pip install fabric Create fabfile.py in your root directory...

Django • Deployment

Global boolean with checkbox:checked and ~ (general sibling combinator)

With the ~ selector, you can easily implement a global accessible boolean without using JavaScript. Add boolean as a checkbox To the very beginning of your document, add as much booleans as you want with a unique id and the hidden attribute set: <input type="checkbox" id="sideba...

CSS • Selectors

Justified navigation bar

The horizontally justified navigation (menu) bar has some number of items that should be justified. The first (left) item has no left margin within the container, the last (right) item has no right margin within the container. The distance between items is equal, independent on the individual item w...

CSS • Inline-Block Layout

Using a password-protected repository

A Subversion repository can be configured so that certain contents or commands are only accessible to certain users. In order to access this restricted content, you will need to specify a username and password. Your username and password can be specified directly as part of the command: $ svn che...

svn • Getting started with svn

Activate developer mode

To activate the developer mode: Log in to the ODOO front end Click on the User Name drop down at the top-right side Select 'About' Click on 'Activate developer mode' from the pop-up window.

odoo-8 • How to activate OpenERP Developer Mode