Tutorial by Examples: co

We can define a function to perform function composition using anonymous function syntax: f ∘ g = x -> f(g(x)) Note that this definition is equivalent to each of the following definitions: ∘(f, g) = x -> f(g(x)) or function ∘(f, g) x -> f(g(x)) end recalling that in Julia,...

The following configuration options should be called on a Rails::Railtie object config.after_initialize: Takes a block which will be run after rails has initialized the application. config.asset_host: This sets the host for the assets. This is useful when using a Content Delivery Network. This i...

The following configuration options can be used for configuring assets config.assets.enabled: Determines whether the asset pipeline is enabled. This defaults to true config.assets.raise_runtime_errors: This enables runtime error checking. It's useful for development mode config.assets.compress:...

Rails allows you to configure what generators are used when running rails generate commands. This method, config.generators takes a block config.generators do |g| g.orm :active_record g.test_framework :test_unit end Here are some of the options OptionDescriptionDefaultassetsCreates asset...

Code First infer the relationship between the two entities using navigation property. This navigation property can be a simple reference type or collection type. For example, we defined Standard navigation property in Student class and ICollection navigation property in Standard class. So, Code Firs...

We have a tree data type like this: data Tree a = Tree a [Tree a] deriving Show And we wish to write a function that assigns a number to each node of the tree, from an incrementing counter: tag :: Tree a -> Tree (a, Int) The long way First we'll do it the long way around, since it illust...

To easily convert all tables in one database, use the following: SET @DB_NAME = DATABASE(); SELECT CONCAT('ALTER TABLE `', table_name, '` ENGINE=InnoDB;') AS sql_statements FROM information_schema.tables WHERE table_schema = @DB_NAME AND `ENGINE` = 'MyISAM' AND `TABLE_TYPE` = '...

Manage Roles Global Roles- Create roles with selected set of Jenkins features e.g. Usually for a development project, 2 roles can be created. Developer- Global role can be set to only Overall : Read ProjectOwner- Global role can be set to Overall : Read This restricts developer and project ...

Generic redirect to https: # Enable Rewrite engine RewriteEngine on # Check if URL does not contain https RewriteCond %{HTTPS} off [NC] # If condition is true, redirect to https RewriteRule (.*) https://%{SERVER_NAME}/$1 [R=301,L] Generic redirect to http: # Enable Rewrite engine Rewr...

Add the following directive before using any other mod_rewrite directive (RewriteRule, RewriteCond, RewriteBase or RewriteMap). RewriteEngine on By default the engine is turned off. mod_rewrite directives found while the engine is turned off are ignored. Enable it from within the virtual host co...

Important: Using the dynamic configuration files (.htaccess) is a big performance hit. When you have access to the static configuration file (httpd.conf or something similar) you should use that instead. In the static configuration file, allow dynamic configuration files to override "Filei...

In this exemple, we want to execute code which is stored in a string format. # the string str <- "1+1" # A string is not an expression. is.expression(str) [1] FALSE eval(str) [1] "1+1" # parse convert string into expressions parsed.str <- parse(text="1+1...

Although Julia is not a purely functional language, it has full support for many of the cornerstones of functional programming: first-class functions, lexical scope, and closures. The fixed-point combinator is a key combinator in functional programming. Because Julia has eager evaluation semantics ...

The SKI combinator system is sufficient to represent any lambda calculus terms. (In practice, of course, lambda abstractions blow up to exponential size when they are translated into SKI.) Due to the simplicity of the system, implementing the S, K, and I combinators is extraordinarily simple: A Dir...

You may need to render some content in view, which is specific to some environment only. To achieve this goal you can use Environment tag helper: <environment names="Development"> <h1>This is heading for development environment</h1> </environment> <envi...

What are local and global scope? All Python variabes which are accessible at some point in code are either in local scope or in global scope. The explanation is that local scope includes all variables defined in the current function and global scope includes variabled defined outside of the curren...

AUTOCOMMIT MySQL automatically commits statements that are not part of a transaction. The results of any UPDATE,DELETE or INSERT statement not preceded with a BEGIN or START TRANSACTION will immediately be visible to all connections. The AUTOCOMMIT variable is set true by default. This can be chan...

import java.awt.EventQueue; import java.awt.GridLayout; import java.awt.event.WindowAdapter; import java.awt.event.WindowEvent; import java.awt.event.WindowListener; import java.util.ArrayList; import java.util.List; import javax.swing.JFrame; import javax.swing.JTextArea; import javax.sw...

If you want to have a table organized in column-store format instead of row store, add INDEX cci CLUSTERED COLUMNSTORE in definition of table: DROP TABLE IF EXISTS Product GO CREATE TABLE Product ( ProductID int, Name nvarchar(50) NOT NULL, Color nvarchar(15), Size nvarchar(5)...

CREATE CLUSTERED COLUMNSTORE INDEX enables you to organize a table in column format: DROP TABLE IF EXISTS Product GO CREATE TABLE Product ( Name nvarchar(50) NOT NULL, Color nvarchar(15), Size nvarchar(5) NULL, Price money NOT NULL, Quantity int ) GO CREATE CLUSTERED C...