30 lines
896 B
Markdown
30 lines
896 B
Markdown
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@name Argument Not Literal
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@category compiler
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@shortDescription Decorator argument is not an object literal
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@description
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To make the metadata extraction in the Angular compiler faster, the decorators `@NgModule`, `@Pipe`, `@Component`, `@Directive`, and `@Injectable` accept only object literals as arguments.
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This is an [intentional change in Ivy](https://github.com/angular/angular/issues/30840#issuecomment-498869540), which enforces stricter argument requirements for decorators than View Engine. Ivy requires this approach because it compiles decorators by moving the expressions into other locations in the class output.
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@debugging
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Move all declarations:
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```typescript
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const moduleDefinition = {...}
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@NgModule(moduleDefinition)
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export class AppModule {
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constructor() {}
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}
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```
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into the decorator:
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```typescript
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@NgModule({...})
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export class AppModule {
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constructor() {}
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}
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```
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