0001    //
0002    //  Switch.swift
0003    //  Commandant
0004    //
0005    //  Created by Neil Pankey on 3/31/15.
0006    //  Copyright (c) 2015 Carthage. All rights reserved.
0007    //
0008    
0009    import Result
0010    
0011    /// Describes a parameterless command line flag that defaults to false and can only
0012    /// be switched on. Canonical examples include `--force` and `--recurse`.
0013    ///
0014    /// For a boolean toggle that can be enabled and disabled use `Option<Bool>`.
0015    public struct Switch
Switch.swift:38
extension Switch: CustomStringConvertible {
Switch.swift:52
public func <| <ClientError> (mode: CommandMode, option: Switch) -> Result<Bool, CommandantError<ClientError>> { {
0016    	/// The key that enables this switch. For example, a key of `verbose` would be
0017    	/// used for a `--verbose` option.
0018    	public let key
Switch.swift:33
		self.key = key
Switch.swift:40
		var options = "--\(key)"
Switch.swift:55
		var enabled = arguments.consumeKey(option.key): String
0019    
0020    	/// Optional single letter flag that enables this switch. For example, `-v` would
0021    	/// be used as a shorthand for `--verbose`.
0022    	///
0023    	/// Multiple flags can be grouped together as a single argument and will split
0024    	/// when parsing (e.g. `rm -rf` treats 'r' and 'f' as inidividual flags).
0025    	public let flag
Switch.swift:32
		self.flag = flag
Switch.swift:41
		if let flag = self.flag {
Switch.swift:56
		if let flag = option.flag {: Character?
0026    
0027    	/// A human-readable string describing the purpose of this option. This will
0028    	/// be shown in help messages.
0029    	public let usage
Switch.swift:34
		self.usage = usage: String
0030    
0031    	public init(flag: Character? = nil, key: String, usage: String) {
0032    		self.flag = flag
0033    		self.key = key
0034    		self.usage = usage
0035    	}
0036    }
0037    
0038    extension Switch: CustomStringConvertible {
0039    	public var description: String {
0040    		var options = "--\(key)"
0041    		if let flag = self.flag {
0042    			options += "|-\(flag)"
0043    		}
0044    		return options
0045    	}
0046    }
0047    
0048    /// Evaluates the given boolean switch in the given mode.
0049    ///
0050    /// If parsing command line arguments, and no value was specified on the command
0051    /// line, the option's `defaultValue` is used.
0052    public func <| <ClientError> (mode: CommandMode, option: Switch) -> Result<Bool, CommandantError<ClientError>> {
0053    	switch mode {
0054    	case let .Arguments(arguments):
0055    		var enabled = arguments.consumeKey(option.key)
0056    		if let flag = option.flag {
0057    			enabled = arguments.consumeBooleanFlag(flag)
0058    		}
0059    		return .Success(enabled)
0060    
0061    	case .Usage:
0062    		return .Failure(informativeUsageError(option.description, usage: option.usage))
0063    	}
0064    }
0065