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How does `val answer: String by project` work? `Project` interface doesn’t have `getValue()` and `setValue()`, so how does it work as a delegate then?

It uses this extension function: <https://github.com/gradle/gradle/blob/344201c165b776ad8f07a21b21942a9780351b0f/subprojects/kotlin-dsl/src/main/kotlin/org/gradle/kotlin/dsl/ProjectExtensions.kt#L193-L197|https://github.com/gradle/gradle/blob/344201c165b776ad8f07a21b21942a9780351b0f/sub[…]-dsl/src/main/kotlin/org/gradle/kotlin/dsl/ProjectExtensions.kt>
```/**
 * Locates a property on [Project].
 */
operator fun Project.provideDelegate(any: Any?, property: KProperty&lt;*&gt;): PropertyDelegate =
    propertyDelegateFor(this, property)```

The mechanism is this: <https://kotlinlang.org/docs/delegated-properties.html#providing-a-delegate>

<@U030S9809PH> where `Project.provideDelegate` is called? I don’t follow :)

&gt; If the object used on the right-hand side of `by` defines `provideDelegate` as a member or extension function, that function will be called to create the property delegate instance.
(<https://kotlinlang.org/docs/delegated-properties.html#providing-a-delegate>)

It just happens automatically if `provideDelegate` exists (and is imported)

If `getValue` exists, then properties using `by` will automatically call through to `getValue(...)`. If `provideDelegate` exists, then properties using `by` will instead call `provideDelegate(...).getValue(...)`. :mage:

The docs give some examples of why you might want to use the latter instead of the former

<@U030S9809PH> I see. `provideDelegate()` references to `propertyDelegateFor()` . Where it is located?

I don’t see such method in `Project` or in `ProjectDelegate` .

<https://github.com/gradle/gradle/blob/344201c165b776ad8f07a21b21942a9780351b0f/subprojects/kotlin-dsl/src/main/kotlin/org/gradle/kotlin/dsl/PropertyDelegate.kt#L45-L50|https://github.com/gradle/gradle/blob/344201c165b776ad8f07a21b21942a9780351b0f/sub[…]n-dsl/src/main/kotlin/org/gradle/kotlin/dsl/PropertyDelegate.kt>