string source =
@"<div class=""entry"">
  <h1>{{title}}</h1>
  <div class=""body"">
    {{body}}
  </div>
</div>";

var template = Handlebars.Compile(source);

var data = new {
    title = "My new post",
    body = "This is my first post!"
};

var result = template(data);

/* Would render:
<div class="entry">
  <h1>My New Post</h1>
  <div class="body">
    This is my first post!
  </div>
</div>
*/

string source =
@"<h2>Names</h2>
{{#names}}
  {{> user}}
{{/names}}";

string partialSource =
@"<strong>{{name}}</strong>";

Handlebars.RegisterTemplate("user", partialSource);

var template = Handlebars.Compile(source);

var data = new {
  names = new [] {
    new {
        name = "Karen"
    },
    new {
        name = "Jon"
    }
  }
};

var result = template(data);

/* Would render:
<h2>Names</h2>
  <strong>Karen</strong>
  <strong>Jon</strong>
*/

Handlebars.RegisterHelper("link_to", (writer, context, parameters) => 
{
    writer.WriteSafeString($"<a href='{context["url"]}'>{context["text"]}</a>");
});

string source = @"Click here: {{link_to}}";

var template = Handlebars.Compile(source);

var data = new {
    url = "https://github.com/rexm/handlebars.net",
    text = "Handlebars.Net"
};

var result = template(data);

/* Would render:
Click here: <a href='https://github.com/rexm/handlebars.net'>Handlebars.Net</a>
*/

Handlebars.RegisterHelper("StringEqualityBlockHelper", (output, options, context, arguments) => 
{
    if (arguments.Length != 2)
    {
        throw new HandlebarsException("{{#StringEqualityBlockHelper}} helper must have exactly two arguments");
    }

    var left = arguments.At<string>(0);
    var right = arguments[1] as string;
    if (left == right) options.Template(output, context);
    else options.Inverse(output, context);
});

var animals = new Dictionary<string, string>() 
{
	{"Fluffy", "cat" },
	{"Fido", "dog" },
	{"Chewy", "hamster" }
};

var template = "{{#each this}}The animal, {{@key}}, {{#StringEqualityBlockHelper @value 'dog'}}is a dog{{else}}is not a dog{{/StringEqualityBlockHelper}}.\r\n{{/each}}";
var compiledTemplate = Handlebars.Compile(template);
string templateOutput = compiledTemplate(animals);

/* Would render
The animal, Fluffy, is not a dog.
The animal, Fido, is a dog.
The animal, Chewy, is not a dog.
*/

public sealed class CustomDateTimeFormatter : IFormatter, IFormatterProvider
{
    private readonly string _format;

    public CustomDateTimeFormatter(string format) => _format = format;

    public void Format<T>(T value, in EncodedTextWriter writer)
    {
        if(!(value is DateTime dateTime)) 
            throw new ArgumentException("supposed to be DateTime");
        
        writer.Write($"{dateTime.ToString(_format)}");
    }

    public bool TryCreateFormatter(Type type, out IFormatter formatter)
    {
        if (type != typeof(DateTime))
        {
            formatter = null;
            return false;
        }

        formatter = this;
        return true;
    }
}

[Fact]
public void DateTimeFormatter(IHandlebars handlebars)
{
    var source = "{{now}}";

    var format = "d";
    var formatter = new CustomDateTimeFormatter(format);
    handlebars.Configuration.FormatterProviders.Add(formatter);

    var template = handlebars.Compile(source);
    var data = new
    {
        now = DateTime.Now
    };
    
    var result = template(data);
    Assert.Equal(data.now.ToString(format), result);
}

[Fact]
public void HelperWithDotSeparatedName()
{
    var source = "{{ one.two }}";
    var handlebars = Handlebars.Create();
    handlebars.Configuration.Compatibility.RelaxedHelperNaming = true;
    handlebars.RegisterHelper("one.two", (context, arguments) => 42);

    var template = handlebars.Compile(source);
    var actual = template(null);
    
    Assert.Equal("42", actual);
}