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Redis-py provides the execute_command method to directly invoke Redis operations. This functionality can be used to access any modules that may not have a supported interface in the redis-py client. For example, you can use the execute_command to list all of the modules loaded into a Redis server:...

EQ checks if two values have the same address of memory: in other words, it checks if the two values are are actually the same, identical object. So, it is can be considered the identity test, and should be applied only to structures: conses, arrays, structures, objects, typically to see if you ...

These three operators implement structural equivalence, that is they check if different, complex objects have equivalent structure with equivalent component. EQUAL behaves like EQL for non-structured data, while for structures built by conses (lists and trees), and the two special types of arrays, ...

Numeric values can compared with = and the other numeric comparison operators (/=, <, <=, >, >=) that ignore the difference in the physical representation of the different types of numbers, and perform the comparison of the corresponding mathematical values. For instance: (= 42 42) T ;...

Common Lisp has 12 type specific operators to compare two characters, 6 of them case sensitives and the others case insensitives. Their names have a simple pattern to make easy to remember their meaning: Case SensitiveCase InsensitiveCHAR=CHAR-EQUALCHAR/=CHAR-NOT-EQUALCHAR<CHAR-LESSPCHAR<=CHA...

Foreword This is a detailed example about how to encrypt and decrypt data with Go. The uses code is shorten, e.g. the error handling is not mentioned. The full working project with error handling and user interface could be found on Github here. Encryption Introduction and data This example de...

The core idea is to use GameObjects to represent singletons, which has multiple advantages: Keeps complexity to a minimum but supports concepts like dependency injection Singletons have a normal Unity lifecycle as part of the Entity-Component system Singletons can be lazy loaded and cached loca...

We can use the componentchanged event to listen for changes to the entity: entity.addEventListener('componentchanged', function (evt) { if (evt.detail.name === 'position') { console.log('Entity has moved from', evt.detail.oldData, 'to', evt.detail.newData, '!'); } });

We can use the child-attached and child-detached events to listen for when the scene attaches or detaches an entity: entity.addEventListener('child-attached', function (evt) { if (evt.detail.el.tagName.toLowerCase() === 'a-box') { console.log('a box element has been attached'); }; }); ...

Updating Multi-Property Component Data To update component data for a multi-property component, we can pass the name of a registered component as the componentName, and pass an object of properties as the value. A string is also acceptable (e.g., type: spot; distance: 30), but objects will save A-F...

We can simply retrieve an entity using DOM APIs. <a-entity id="mario"></a-entity> var el = document.querySelector('#mario');

For example, if we wanted to grab an entity’s three.js camera object or material object, we could reach into its components var camera = document.querySelector('a-entity[camera]').components.camera.camera; var material = document.querySelector('a-entity[material]').components.material.material; ...

A system is registered similarly to a A-Frame component. If the system name matches a component name, then the component will have a reference to the system as this.system: AFRAME.registerSystem('my-component', { schema: {}, // System schema. Parses into `this.data`. init: function () { ...

An instantiated system can be accessed through the scene: document.querySelector('a-scene').systems[systemName]; Registered system prototypes can be accessed through AFRAME.systems.

Systems can help separate logic and behavior from data if desired. We let systems handle the heavy lifting, and components only worry about managing its data through its lifecycle methods: AFRAME.registerSystem('my-component', { createComplexObject: function (data) { // Do calculations ...

There is no strict API for defining how systems manage components. A common pattern is to have components subscribe themselves to the system. The system then has references to all of its components: AFRAME.registerSystem('my-component', { init: function () { this.entities = []; }, ...

AFRAME.registerComponent (name, definition) Register an A-Frame component. We must register components before we use them anywhere in . Meaning from an HTML file, components should come in order before . {string} name - Component name. The component’s public API as represented through an HTML at...

The schema is an object that defines and describes the property or properties of the component. The schema’s keys are the names of the property, and the schema’s values define the types and values of the property (in case of a multi-property component): Defining schema in your component AFRAME.reg...

Property types primarily define how the schema parses incoming data from the DOM for each property. The parsed data will then be available via the data property on the component's prototype. Below are A-Frame's built-in property types: Property TypeDescriptionDefault ValuearrayParses comma-separ...

A component’s members and methods can be accessed through the entity from the .components object. Look up the component from the entity’s map of components, and we’ll have access to the component’s internals. Consider this example component: AFRAME.registerComponent('foo', { init: function () { ...