Pipe documentation does not explain the default value of `standalone`

[raphinesse]

Describe the problem that you experienced

In fact, https://angular.dev/api/core/Pipe is missing details about the configuration object of the annotation entirely. the individual options are documented at

angular/packages/core/src/metadata/directives.ts

Lines 729 to 757 in 9fa77af

	export interface Pipe {
	/**
	* The pipe name to use in template bindings.
	* Typically uses lowerCamelCase
	* because the name cannot contain hyphens.
	*/
	name: string;
	/**
	* When true, the pipe is pure, meaning that the
	* `transform()` method is invoked only when its input arguments
	* change. Pipes are pure by default.
	*
	* If the pipe has internal state (that is, the result
	* depends on state other than its arguments), set `pure` to false.
	* In this case, the pipe is invoked on each change-detection cycle,
	* even if the arguments have not changed.
	*/
	pure?: boolean;
	/**
	* Angular pipes marked as `standalone` do not need to be declared in an NgModule. Such
	* pipes don't depend on any "intermediate context" of an NgModule (ex. configured providers).
	*
	* More information about standalone components, directives, and pipes can be found in [this
	* guide](guide/components/importing).
	*/
	standalone?: boolean;
	}

but that neither has info about the default for standalone, not appears in the rendered docs.

Enter the URL of the topic with the problem

https://angular.dev/api/core/Pipe

Describe what you were looking for in the documentation

No response

Describe the actions that led you to experience the problem

No response

Describe what you want to experience that would fix the problem

No response

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Provide any additional information here in as much as detail as you can

[VaradGupta23]

Here’s the missing piece the issue is pointing at, explained plainly.

What is the default value of standalone for @pipe?

standalone defaults to false.

That means:

A pipe is not standalone by default

It must be declared in an NgModule unless you explicitly set standalone: true

This behavior is consistent with how standalone support was introduced in Angular (v14+): nothing becomes standalone unless you opt in.

Why this is confusing in the docs

The rendered docs at
https://angular.dev/api/core/Pipe
don’t list the decorator options at all

The source interface (Pipe in directives.ts) lists standalone?: boolean but:

Doesn’t mention the default

Uses ?, which hides the fact that Angular applies an implicit default

This makes it unclear whether:

standalone defaults to true

Or defaults to false

Or depends on Angular version

In reality, Angular treats it as false unless explicitly set.

Practical behavior (what actually happens)
Default (non-standalone)
@pipe({
name: 'myPipe'
})
export class MyPipe {
transform(value: string) {
return value.toUpperCase();
}
}

Must be declared in an NgModule:

@NgModule({
declarations: [MyPipe]
})
export class SharedModule {}

Standalone pipe
@pipe({
name: 'myPipe',
standalone: true
})
export class MyPipe {
transform(value: string) {
return value.toUpperCase();
}
}

Can be imported directly:

@component({
standalone: true,
imports: [MyPipe],
template: {{ 'hello' | myPipe }}
})
export class TestComponent {}

Why the GitHub issue is valid

The issue is correct because:

The docs don’t describe any of the decorator options

The default value of standalone is undocumented

Users reading only angular.dev cannot infer required NgModule usage

The referenced fix (docs(core): add comprehensive documentation for Pipe decorator) is meant to close this exact gap.

TL;DR

standalone defaults to false

Pipes behave like pre-Angular-14 pipes unless you opt in

The docs were incomplete, and the issue correctly flags that

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