0001    //
0002    //  HelpCommand.swift
0003    //  Commandant
0004    //
0005    //  Created by Justin Spahr-Summers on 2014-10-10.
0006    //  Copyright (c) 2014 Carthage. All rights reserved.
0007    //
0008    
0009    import Foundation
0010    import Result
0011    
0012    /// A basic implementation of a `help` command, using information available in a
0013    /// `CommandRegistry`.
0014    ///
0015    /// If you want to use this command, initialize it with the registry, then add
0016    /// it to that same registry:
0017    ///
0018    /// 	let commands: CommandRegistry<MyErrorType> = …
0019    /// 	let helpCommand = HelpCommand(registry: commands)
0020    /// 	commands.register(helpCommand)
0021    public struct HelpCommand<ClientError
HelpCommand.swift:22
	public typealias Options = HelpOptions<ClientError>
HelpCommand.swift:27
	private let registry: CommandRegistry<ClientError>
HelpCommand.swift:31
	public init(registry: CommandRegistry<ClientError>) {
: ErrorType>: CommandType {
0022    	public typealias Options
HelpCommand.swift:35
	public func run(options: Options) -> Result<(), ClientError> {
 = HelpOptions<ClientError>
0023    
0024    	public let verb = "help"
0025    	public let function = "Display general or command-specific help"
0026    
0027    	private let registry
HelpCommand.swift:32
		self.registry = registry
HelpCommand.swift:50
		let maxVerbLength = self.registry.commands.map { $0.verb.characters.count }.maxElement() ?? 0
HelpCommand.swift:52
		for command in self.registry.commands {
: CommandRegistry<ClientError>
0028    
0029    	/// Initializes the command to provide help from the given registry of
0030    	/// commands.
0031    	public init(registry: CommandRegistry<ClientError>) {
0032    		self.registry = registry
0033    	}
0034    
0035    	public func run(options: Options) -> Result<(), ClientError> {
0036    		if let verb = options.verb {
0037    			if let command = self.registry[verb] {
0038    				print(command.function)
0039    				if let usageError = command.usage() {
0040    					print("\n\(usageError)")
0041    				}
0042    				return .Success(())
0043    			} else {
0044    				fputs("Unrecognized command: '\(verb)'\n", stderr)
0045    			}
0046    		}
0047    
0048    		print("Available commands:\n")
0049    
0050    		let maxVerbLength = self.registry.commands.map { $0.verb.characters.count }.maxElement() ?? 0
0051    
0052    		for command in self.registry.commands {
0053    			let padding = Repeat<Character>(count: maxVerbLength - command.verb.characters.count, repeatedValue: " ")
0054    			print("   \(command.verb)\(String(padding))   \(command.function)")
0055    		}
0056    
0057    		return .Success(())
0058    	}
0059    }
0060    
0061    public struct HelpOptions
HelpCommand.swift:22
	public typealias Options = HelpOptions<ClientError>
HelpCommand.swift:68
	private static func create(verb: String) -> HelpOptions {
<ClientError: ErrorType>: OptionsType {
0062    	private let verb
HelpCommand.swift:65
		self.verb = verb
: String?
0063    	
0064    	private init
HelpCommand.swift:69
		return self.init(verb: (verb == "" ? nil : verb))
(verb: String?) {
0065    		self.verb = verb
0066    	}
0067    
0068    	private static func create(verb: String) -> HelpOptions {
0069    		return self.init(verb: (verb == "" ? nil : verb))
0070    	}
0071    
0072    	public static func evaluate(m: CommandMode) -> Result<HelpOptions, CommandantError<ClientError>> {
0073    		return create
0074    			<*> m <| Argument(defaultValue: "", usage: "the command to display help for")
0075    	}
0076    }
0077