RequiredConstraint
public struct RequiredConstraint<T, E> : Constraint where T : Collection, E : Error
A Constraint
that check whether the input collection is empty.
enum Failure: Error {
case required
case invalidEmail
}
let constraint = RequiredConstraint<String, Failure>(error: .required)
let result = constraint.evaluate(with: "hello@nsagora.com")
-
Returns a new
RequiredConstraint
instance.enum Failure: Error { case required case invalidEmail }
let constraint = RequiredConstraint<String, Failure>(error: .required) let result = constraint.evaluate(with: "hello@nsagora.com")
Declaration
Swift
public init(error: E)
Parameters
error
An
Error
that describes why the evaluation has failed. -
Returns a new
RequiredConstraint
instance.enum Failure: Error { case required case invalidEmail }
let constraint = RequiredConstraint<String, Failure> { _ in .required } let result = constraint.evaluate(with: "hello@nsagora.com")
Declaration
Swift
public init(errorBuilder: @escaping (T) -> E)
Parameters
error
A generic closure that dynamically builds an
Error
to describe why the evaluation has failed. -
Returns a new
RequiredConstraint
instance.enum Failure: Error { case required case invalidEmail }
let constraint = RequiredConstraint<String, Failure> { .required } let result = constraint.evaluate(with: "hello@nsagora.com")
Declaration
Swift
public init(errorBuilder: @escaping () -> E)
Parameters
error
A generic closure that dynamically builds an
Error
to describe why the evaluation has failed.