Files
swiftpm-mustache/Sources/HummingbirdMustache/CustomRenderable.swift
2021-05-03 17:05:17 +01:00

39 lines
1.3 KiB
Swift

//===----------------------------------------------------------------------===//
//
// This source file is part of the Hummingbird server framework project
//
// Copyright (c) 2021-2021 the Hummingbird authors
// Licensed under Apache License v2.0
//
// See LICENSE.txt for license information
// See hummingbird/CONTRIBUTORS.txt for the list of Hummingbird authors
//
// SPDX-License-Identifier: Apache-2.0
//
//===----------------------------------------------------------------------===//
import Foundation
/// Allow object to override standard hummingbird type rendering which uses
/// `String(describing)`.
public protocol HBMustacheCustomRenderable {
/// Custom rendered version of object
var renderText: String { get }
/// Whether the object is a null object. Used when scoping sections
var isNull: Bool { get }
}
extension HBMustacheCustomRenderable {
/// default version returning the standard rendering
var renderText: String { String(describing: self) }
/// default version returning false
var isNull: Bool { false }
}
/// Extend NSNull to conform to `HBMustacheCustomRenderable` to avoid outputting `<null>` and returning
/// a valid response for `isNull`
extension NSNull: HBMustacheCustomRenderable {
public var renderText: String { "" }
public var isNull: Bool { true }
}