feat: Working on new implementation experiments.

Sources/main.swift

@@ -33,97 +33,62 @@ enum YamlItem {
   case boolean(Bool)
   case date(year: Int, month: Int, day: Int)
   case string(String)
+  case listItem(String)
 
-  private static let dateParser = Parse(input: Substring.self) {
+  private static let dateParser = Parse(input: Substring.UTF8View.self) {
     Digits(4)
-    "-"
+    "-".utf8
     Digits(2)
-    "-"
+    "-".utf8
     Digits(2)
   }.map { Self.date(year: $0.0, month: $0.1, day: $0.2) }
 
-  private static let booleanParser = Parse(input: Substring.self) {
+  private static let booleanParser = Parse(input: Substring.UTF8View.self) {
     Bool.parser()
   }.map { Self.boolean($0) }
 
-  private static let quotedString = Parse(input: Substring.self) {
-    "\""
-    PrefixUpTo("\"")
-    "\""
+  private static let quotedString = Parse(input: Substring.UTF8View.self) {
+    "\"".utf8
+    PrefixUpTo("\"".utf8)
+    "\"".utf8
   }
 
-  private static let stringParser = Parse(input: Substring.self) {
+  private static let stringParser = Parse(input: Substring.UTF8View.self) {
     OneOf {
       quotedString
       Rest()
     }
-  }.map { Self.string(String($0)) }
+  }.map { Self.string(String(Substring($0))) }
+
+  private static let listItemParser = Parse(input: Substring.UTF8View.self) {
+    Skip { Whitespace() }
+    "- ".utf8
+    Rest()
+  }.map { Self.listItem(String(Substring($0))) }
 
   static let parser = OneOf {
     dateParser
     booleanParser
+    listItemParser
     stringParser
   }
 }
 
-enum YamlLine {
-  case keyValue(String, YamlItem)
-  case list(String, [String])
-
-  static let parser = OneOf {
-    listParser
-    keyValueParser
-  }
-
-  static let keyParser = Parse(input: Substring.self) {
-    PrefixUpTo(":")
-    ":"
-  }.map(String.init)
-
-  static let keyValueParser = Parse(input: Substring.self) {
-    PrefixUpTo(":").map(String.init)
-    ": "
-    YamlItem.parser
-  }.map { YamlLine.keyValue($0.0, $0.1) }
-
-  static let listLineParser = Parse(input: Substring.self) {
-    Skip { PrefixThrough("- ") }
-    PrefixUpTo("\n").map(String.init)
-    "\n"
-  }
-
-  static let listParser = Parse(input: Substring.self) {
-    PrefixUpTo(":\n").map(String.init)
-    ":\n"
-    Many {
-      Skip { PrefixThrough("- ") }
-      PrefixUpTo("\n").map(String.init)
-      "\n"
-    }
-  }
-  .map { YamlLine.list($0.0, $0.1) }
-}
-
 let yamlBlockParser = Parse(input: Substring.UTF8View.self) {
   "---\n".utf8
   Many {
-    PrefixUpTo("\n".utf8)
+    PrefixUpTo(":".utf8)
+    ":".utf8
+    Optionally { YamlItem.parser }
+    // PrefixUpTo("\n".utf8)
     // From(.substring) { YamlLine.parser }
   } separator: {
     "\n".utf8
-  }
-  "\n".utf8
+  } terminator: {
+    // "\n".utf8
     "---".utf8
   }
-
-// let yamlLineParser = Parse(input: Substring.UTF8View.self) {
-//   PrefixUpTo(":".utf8).map(String.init)
-//   ":".utf8
-//   OneOf {
-//     PrefixUpTo("\n".utf8)
-//     Rest()
-//   }.map(String.init)
-// }
+}
 
 let stringLine = #"author: "Michael Housh""#
 // let parsedLine = try yamlLineParser.parse(stringLine[...].utf8)
@@ -140,19 +105,29 @@ try print(YamlItem.parser.parse(dateItem[...]))
 try print(YamlItem.parser.parse(boolItem[...]))
 
 let kvLine = "author: Michael Housh"
-var listLine = """
-test:
+var listLine = #"""
   - HVAC
   - General
   - Programming
 
-"""[...]
+"""#[...]
 
-try print(YamlLine.parser.parse(kvLine[...]))
-try print(YamlLine.parser.parse(&listLine))
-print(listLine)
+struct YamlList: Parser {
 
-// try print(YamlItem.parser.parse(listItem[...]))
+  var body: some Parser<Substring.UTF8View, [String]> {
+    Many(into: [String]()) { array, string in
+      array.append(string)
+    } element: {
+      Whitespace()
+      "-".utf8
+      Whitespace()
+      PrefixUpTo("\n".utf8).map(.string)
+      "\n".utf8
+    }
+  }
+}
+
+try print(YamlList().parse(listLine))
 
 var yamlLines = """
 author: Michael Housh
@@ -163,28 +138,71 @@ test:
 
 """[...]
 
-let lineParser = Many {
-  YamlLine.parser
-} separator: {
-  "\n"
+struct SimpleYamlValue: Parser {
+  enum Output: Equatable {
+    case array([String])
+    case bool(Bool)
+    case date(year: Int, month: Int, day: Int)
+    case string(String)
   }
 
-try print(lineParser.parse(yamlLines))
+  var body: some Parser<Substring.UTF8View, Output> {
+    OneOf {
+      // YamlList().map { Output.array($0) }
+      DateParser()
+      Bool.parser().map(.case(Output.bool))
+      PrefixUpTo("\n".utf8).map(.string).map(.case(Output.string))
+      Rest().map(.string).map(.case(Output.string))
+    }
+  }
 
-// let lines = try yamlBlockParser.parse(yamlString[...].utf8)
-//
-// for line in lines {
-//   print("line: \(String(line)!)")
-//   if let parsed = try? YamlLine.keyValueParser.parse(Substring(line)) {
+  struct DateParser: Parser {
+    var body: some Parser<Substring.UTF8View, Output> {
+      Parse {
+        Digits(4)
+        "-".utf8
+        Digits(2)
+        "-".utf8
+        Digits(2)
+      }.map(.case(Output.date))
+    }
+  }
+}
+
+// This works, but doesn't handle lists well.
+struct SimpleYamlParser: Parser {
+  var body: some Parser<Substring.UTF8View, [String: SimpleYamlValue.Output]> {
+    Many(into: [String: SimpleYamlValue.Output]()) { (dict: inout [String: SimpleYamlValue.Output], pair: (String, SimpleYamlValue.Output)) in
+      let (key, value) = pair
+      dict[key] = value
+    } element: {
+      PrefixUpTo(":".utf8).map(.string)
+      ":".utf8
+      Whitespace()
+      SimpleYamlValue()
+    } separator: {
+      "\n".utf8
+    } terminator: {
+      End()
+    }
+  }
+}
+
+let simpleYamlString = #"""
+author: Michael Housh
+copy: true
+draft: false
+date: 2023-10-21
+lastmod: 2023-10-21
+image: banner.png
+featuredImage: banner.png
+"""#
+
+let parsed = try SimpleYamlParser().parse(simpleYamlString[...].utf8)
 // print(parsed)
-//   } else {
-//     if let key = try? YamlLine.keyParser.parse(Substring(line)) {
-//       print("found key: \(String(key))")
-//     } else {
-//       print("not key value.")
-//     }
-//   }
-// }
 
-// print(lines.map(String.init))
-// print(lines)
+for (key, value) in parsed {
+  print("\(key): \(value)")
+}
+
+// try print(SimpleYamlParser().parse(simpleYamlString[...].utf8))