Swift: Dictionary の要素の削除

プログラム

text_delete.swift

// --------------------------------------------------------------------
//	  text_delete.swift
//
//						  Oct/29/2024
//
// --------------------------------------------------------------------
import Foundation

// --------------------------------------------------------------------
func textWriteProc(fileOut: String, dictAA: [String: [String: Any]]) {
	do {
		let fileURL = URL(fileURLWithPath: fileOut)
		var strOut = ""
		
		for (key, unit) in dictAA {
			if let name = unit["name"] as? String,
			   let population = unit["population"] as? Int,
			   let dateMod = unit["date_mod"] as? String {
				strOut += "\(key)\t\(name)\t\(population)\t\(dateMod)\n"
			}
		}
		
		try strOut.write(to: fileURL, atomically: true, encoding: .utf8)
	} catch {
		fputs("*** error *** in textWriteProc ***\n", stderr)
		fputs("\(error)\n", stderr)
	}
}

// --------------------------------------------------------------------
func textReadProc(fileIn: String) -> [String:[String:Any]] {
	var dict = [String: [String: Any]]()
	
	let fpIn = try! String(contentsOfFile: fileIn, encoding: .utf8)
	let lines = fpIn.components(separatedBy: .newlines)
	
	for line in lines {
		let cols = line.trimmingCharacters(in: .whitespacesAndNewlines).components(separatedBy: "\t")
		if cols.count >= 4, cols[0].hasPrefix("t") {
			if let population = Int(cols[2]) {
				dict[cols[0]] = ["name": cols[1], "population": population, "date_mod": cols[3]]
			} else {
				print("*** error *** \(fileIn) ***")
				print("*** \(line) ***")
			}
		}
	}
	
	return dict
}

// --------------------------------------------------------------------
func dictDisplayProc(dict: [String:[String:Any]]) {
	for (key, value) in dict.sorted(by: { $0.key < $1.key }) {
		let name = value["name"]!
		let population = value["population"]!
		let dateMod = value["date_mod"]!
		print("\(key)\t\(name)\t\(population)\t\(dateMod)")
	}
}

// --------------------------------------------------------------------
print("*** 開始 ***")

guard CommandLine.arguments.count > 1 else {
	print("入力ファイル名を指定してください")
	exit(1)
}

let fileIn = CommandLine.arguments[1]
let keyIn = CommandLine.arguments[2]

print(fileIn) 
print(keyIn) 

var dict = textReadProc(fileIn: fileIn)

if dict.keys.contains(keyIn) {
	let value = dict[keyIn]!
	let name_target = value["name"]!
	print(name_target)

	dict.removeValue(forKey: keyIn)

	dictDisplayProc(dict: dict)
	textWriteProc(fileOut: fileIn, dictAA: dict)
	}

print("*** 終了 ***")
// --------------------------------------------------------------------

実行コマンド

swift text_delete.swift cities.txt t2387

確認したバージョン

$ swift --version
Swift version 6.0.1 (swift-6.0.1-RELEASE)
Target: x86_64-unknown-linux-gnu