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# LaunchConstraintBuilder

A custom parameter attribute that constructs launch constraints from closures.

```
@resultBuilder struct LaunchConstraintBuilder
```

## Topics

### Type Methods

[`static func buildBlock([any LaunchConstraint]...) -> [any LaunchConstraint]`](/documentation/LightweightCodeRequirements/LaunchConstraintBuilder/buildBlock(_:))

Builds flat array from a variadic set of arrays

[`static func buildEither(first: [any LaunchConstraint]) -> [any LaunchConstraint]`](/documentation/LightweightCodeRequirements/LaunchConstraintBuilder/buildEither(first:))

Produces content for a conditional statement in a multi-statement closure when the condition is true

[`static func buildEither(second: [any LaunchConstraint]) -> [any LaunchConstraint]`](/documentation/LightweightCodeRequirements/LaunchConstraintBuilder/buildEither(second:))

Produces content for a conditional statement in a multi-statement closure when the condition is false

[`static func buildExpression(any LaunchConstraint) -> [any LaunchConstraint]`](/documentation/LightweightCodeRequirements/LaunchConstraintBuilder/buildExpression(_:)-5tl61)

Builds an expression within the builder

[`static func buildExpression([any LaunchConstraint]) -> [any LaunchConstraint]`](/documentation/LightweightCodeRequirements/LaunchConstraintBuilder/buildExpression(_:)-6l0k6)

Builds an expression within the builder

[`static func buildOptional([any LaunchConstraint]?) -> [any LaunchConstraint]`](/documentation/LightweightCodeRequirements/LaunchConstraintBuilder/buildOptional(_:))

Produces content for a conditional statement in a multi-statement closure when the condition is true and has no else option

---

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