- Oct 2024
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www.youtube.com www.youtube.com
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23:10 MMT is not a new system or theory. It simply explains what happens today.
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- Jan 2024
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mongoosejs.com mongoosejs.com
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Instance methods Instances of Models are documents. Documents have many of their own built-in instance methods. We may also define our own custom document instance methods. // define a schema const animalSchema = new Schema({ name: String, type: String }, { // Assign a function to the "methods" object of our animalSchema through schema options. // By following this approach, there is no need to create a separate TS type to define the type of the instance functions. methods: { findSimilarTypes(cb) { return mongoose.model('Animal').find({ type: this.type }, cb); } } }); // Or, assign a function to the "methods" object of our animalSchema animalSchema.methods.findSimilarTypes = function(cb) { return mongoose.model('Animal').find({ type: this.type }, cb); }; Now all of our animal instances have a findSimilarTypes method available to them. const Animal = mongoose.model('Animal', animalSchema); const dog = new Animal({ type: 'dog' }); dog.findSimilarTypes((err, dogs) => { console.log(dogs); // woof }); Overwriting a default mongoose document method may lead to unpredictable results. See this for more details. The example above uses the Schema.methods object directly to save an instance method. You can also use the Schema.method() helper as described here. Do not declare methods using ES6 arrow functions (=>). Arrow functions explicitly prevent binding this, so your method will not have access to the document and the above examples will not work.
Certainly! Let's break down the provided code snippets:
1. What is it and why is it used?
In Mongoose, a schema is a blueprint for defining the structure of documents within a collection. When you define a schema, you can also attach methods to it. These methods become instance methods, meaning they are available on the individual documents (instances) created from that schema.
Instance methods are useful for encapsulating functionality related to a specific document or model instance. They allow you to define custom behavior that can be executed on a specific document. In the given example, the
findSimilarTypes
method is added to instances of theAnimal
model, making it easy to find other animals of the same type.2. Syntax:
Using
methods
object directly in the schema options:javascript const animalSchema = new Schema( { name: String, type: String }, { methods: { findSimilarTypes(cb) { return mongoose.model('Animal').find({ type: this.type }, cb); } } } );
Using
methods
object directly in the schema:javascript animalSchema.methods.findSimilarTypes = function(cb) { return mongoose.model('Animal').find({ type: this.type }, cb); };
Using
Schema.method()
helper:javascript animalSchema.method('findSimilarTypes', function(cb) { return mongoose.model('Animal').find({ type: this.type }, cb); });
3. Explanation in Simple Words with Examples:
Why it's Used:
Imagine you have a collection of animals in your database, and you want to find other animals of the same type. Instead of writing the same logic repeatedly, you can define a method that can be called on each animal instance to find similar types. This helps in keeping your code DRY (Don't Repeat Yourself) and makes it easier to maintain.
Example:
```javascript const mongoose = require('mongoose'); const { Schema } = mongoose;
// Define a schema with a custom instance method const animalSchema = new Schema({ name: String, type: String });
// Add a custom instance method to find similar types animalSchema.methods.findSimilarTypes = function(cb) { return mongoose.model('Animal').find({ type: this.type }, cb); };
// Create the Animal model using the schema const Animal = mongoose.model('Animal', animalSchema);
// Create an instance of Animal const dog = new Animal({ type: 'dog', name: 'Buddy' });
// Use the custom method to find similar types dog.findSimilarTypes((err, similarAnimals) => { console.log(similarAnimals); }); ```
In this example,
findSimilarTypes
is a custom instance method added to theAnimal
schema. When you create an instance of theAnimal
model (e.g., a dog), you can then callfindSimilarTypes
on that instance to find other animals with the same type. The method uses thethis.type
property, which refers to the type of the current animal instance. This allows you to easily reuse the logic for finding similar types across different instances of theAnimal
model.
Tags
Annotators
URL
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- Nov 2022
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stackoverflow.com stackoverflow.com
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session = ActionDispatch::Integration::Session.new(Rails.application) response = session.post("/mypath", my_params: "go_here")
worked for me
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I used the above to test what happens to the user if a POST happens in another session (via WebSockets), so a form wouldn't cut it.
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- Sep 2021
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spin.atomicobject.com spin.atomicobject.com
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An extensible plugin architecture allows for customizing your workflow or even making Yarn a package manager for non-JavaScript projects.
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- Jun 2021
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www.mutuallyhuman.com www.mutuallyhuman.com
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For me the diagrams make it easier to talk about what the tests do without getting bogged down by how they do it.
Tags
- communication: use the right level of detail
- communication: focus on what is important
- describe the what without getting bogged down by how (implementation details; too detailed)
- focus on what it should do, not on how it should do it (implementation details; software design)
- too detailed
- communication: effective communication
Annotators
URL
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- Nov 2020
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developer.mozilla.org developer.mozilla.org
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Fallback values aren't used to fix the browser compatibility. If the browser doesn't support CSS custom Properties, the fallback value won't help.
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github.com github.com
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Tell you why tree-shaking fails, if it does.
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What it doesn't do
Tags
Annotators
URL
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- Oct 2020
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Note that these are not hyperlinks; these URIs are used for identification. This is a machine-readable way to say “this is HTML”. In particular, software does not usually need to fetch these resources, and certainly does not need to fetch the same one over and over!
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github.com github.com
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JSX is an XML-like syntax extension to EcmaScript (https://facebook.github.io/jsx/). It is not a language or runtime.
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- Jul 2020
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The carefully crafted Medium story can give the appearance that- at the nadir of your professional life- you are above it all, you are concerned about others, and you are a soulful human being moving on to an even more lucrative future.
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- May 2020
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jamstack.org jamstack.org
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When is your site not built with the Jamstack? Any project that relies on a tight coupling between client and server is not built with the Jamstack.
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en.wikipedia.org en.wikipedia.org
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In natural languages, some apparent tautologies may have non-tautological meanings in practice. In English, "it is what it is" is used to mean 'there is no way of changing it'.[1] In Tamil, vantaalum varuvaan literally means 'if he comes, he will come', but really means 'he just may come'.[2]
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- Apr 2020
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en.wikipedia.org en.wikipedia.org
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The term "ad hoc" in this context is not intended to be pejorative; it refers simply to the fact that this type of polymorphism is not a fundamental feature of the type system.
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- Nov 2019
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reasonml.github.io reasonml.github.io
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Reason is not a new language; it's a new syntax and toolchain powered by the battle-tested language, OCaml.
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