Loading YAML

uses VSoft.YAML;

var
  doc: IYAMLDocument;
  yaml: string;
begin
  yaml := 'name: John Doe' + sLineBreak +
          'age: 30' + sLineBreak +
          'city: New York';
          
  doc := TYAML.LoadFromString(yaml);
  
  WriteLn('Name: ', doc.Root.Values['name'].AsString);
  WriteLn('Age: ', doc.Root.Values['age'].AsInteger);
end;

Creating YAML Documents

var
  doc: IYAMLDocument;
  person: IYAMLMapping;
begin
  doc := TYAML.CreateMapping;
  person := doc.Root.AsMapping;
  
  person.AddOrSetValue('name', 'Jane Smith');
  person.AddOrSetValue('age', 25);
  
  WriteLn(TYAML.WriteToString(doc));
end;

Working with Collections

var
  doc: IYAMLDocument;
  fruits: IYAMLSequence;
begin
  yaml := 'fruits:' + sLineBreak +
          '  - apple' + sLineBreak +
          '  - banana' + sLineBreak +
          '  - orange';
          
  doc := TYAML.LoadFromString(yaml);
  fruits := doc.Root.Values['fruits'].AsSequence;
  
  for i := 0 to fruits.Count - 1 do
    WriteLn('Fruit: ', fruits.Items[i].AsString);
end;

Multiple Documents

var
  documents: TArray<IYAMLDocument>;
  doc1, doc2: IYAMLDocument;
  yamlContent: string;
begin
  // Create multiple documents
  doc1 := TYAML.CreateMapping;
  doc1.AsMapping.AddOrSetValue('name', 'Config 1');
  doc1.AsMapping.AddOrSetValue('version', 1);
  
  doc2 := TYAML.CreateMapping;
  doc2.AsMapping.AddOrSetValue('name', 'Config 2');
  doc2.AsMapping.AddOrSetValue('version', 2);
  
  // Write multiple documents
  SetLength(documents, 2);
  documents[0] := doc1;
  documents[1] := doc2;
  
  yamlContent := TYAML.WriteAllToString(documents);
  WriteLn('Multi-document YAML:');
  WriteLn(yamlContent);
  
  // Load multiple documents
  documents := TYAML.LoadAllFromString(yamlContent);
  WriteLn('Loaded ', Length(documents), ' documents');
end;

Working with Tags

var
  doc: IYAMLDocument;
  root: IYAMLMapping;
begin
  doc := TYAML.CreateMapping;
  root := doc.AsMapping;
  
  // Add values with explicit tags
  root.AddOrSetValue('port', '8080', '!!int');     // Force integer type
  root.AddOrSetValue('name', 'server', '!!str');   // Force string type
  root.AddOrSetValue('config', configData, '!app!config'); // Custom tag
  
  WriteLn(TYAML.WriteToString(doc));
end;

Writing to JSON

var
  doc: IYAMLDocument;
  person: IYAMLMapping;
  jsonOutput: string;
begin
  // Create a YAML document
  doc := TYAML.CreateMapping;
  person := doc.Root.AsMapping;
  
  person.AddOrSetValue('name', 'John Doe');
  person.AddOrSetValue('age', 30);
  person.AddOrSetValue('city', 'New York');
  
  // Export to compact JSON
  doc.Options.PrettyPrint := false;
  jsonOutput := TYAML.WriteToJSONString(doc);
  WriteLn('Compact JSON: ', jsonOutput);
  // Output: {"name":"John Doe","age":30,"city":"New York"}
  
  // Export to pretty-printed JSON
  doc.Options.PrettyPrint := true;
  doc.Options.IndentSize := 2;
  jsonOutput := TYAML.WriteToJSONString(doc);
  WriteLn('Pretty JSON:');
  WriteLn(jsonOutput);
  // Output:
  // {
  //   "name": "John Doe",
  //   "age": 30,
  //   "city": "New York"
  // }
  
  // Write JSON to file
  TYAML.WriteToJSONFile(doc, 'output.json');
end;

Converting YAML to JSON

var
  yamlDoc: IYAMLDocument;
  yamlContent: string;
  jsonOutput: string;
begin
  // Load YAML content
  yamlContent := 'employees:' + sLineBreak +
                 '  - name: Alice' + sLineBreak +
                 '    role: Developer' + sLineBreak +
                 '  - name: Bob' + sLineBreak +
                 '    role: Designer';
                 
  yamlDoc := TYAML.LoadFromString(yamlContent);
  
  // Convert to JSON with pretty printing
  yamlDoc.Options.PrettyPrint := true;
  jsonOutput := TYAML.WriteToJSONString(yamlDoc);
  
  WriteLn('YAML to JSON conversion:');
  WriteLn(jsonOutput);
  // Output:
  // {
  //   "employees": [
  //     {
  //       "name": "Alice",
  //       "role": "Developer"
  //     },
  //     {
  //       "name": "Bob",
  //       "role": "Designer"
  //     }
  //   ]
  // }
end;

Exact Numbers

Numbers are written exactly as they were read or added, in JSON and YAML, rather than going through Int64 or Double. For values that no Delphi type holds, such as a SQL DECIMAL(38,10), add the number from its text with AddOrSetNumber (on a sequence, AddNumber). The text must be a JSON number (-, digits, an optional fraction and an optional exponent), or EConvertError is raised. Like a parsed number, it is an integer unless it has a fraction or an exponent.

var
  doc: IYAMLDocument;
  row: IYAMLMapping;
  price: Currency;
begin
  doc := TYAML.CreateMapping;
  row := doc.AsMapping;
  price := 19.99;

  row.AddOrSetValue('id', UInt64(High(UInt64)));
  row.AddOrSetCurrencyValue('price', price);
  row.AddOrSetNumber('total', '1234567890123456789012345678.9012345678');
  row.AddOrSetValue('note', '');   // an empty string
  row.AddOrSetNull

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