jsommr/NustacheMetaData.cs

## NustacheMetaData.cs
using System.Linq;
using Nustache.Core;

static ILookup<string, string> GetMetadata(string templateContent) {
	// All metadata are written as {{! key: value }}. {{! ... }} is a comment in Mustache.
	// This function uses the possibility to alter start and end delimiters to scan for {{! }}
	// instead of {{ }}. With {{! as start delimiter, {{!! becomes a comment. I don't think
	// you need comments in this case, but I think this is a neat way to include metadata in
	// the templates.
	return new Scanner("{{!", "}}")
		.Scan (templateContent)
		.OfType<VariableReference> ()
		.Select (varRef => varRef.Path.Split(':'))
		.Where (x => x.Length == 2)
		.ToLookup(x => x[0].Trim(), x => x[1].Trim());
}

/*
Usage
=====

template:
  {{! from: admin@mywebsite.org }}
  {{! subject: Regarding your browser history }}
  <body>
    <h1>Dear {{ name }}</h1>
    <p>.....</p>
  </body>
*/

var tmpl = "{{! from: admin@mywebsite.org }}\n  {{! subject: Regarding your browser history }}\n  <body>\n    <h1>Dear {{ name }}</h1>\n    <p>.....</p>\n  </body>";
var metadata = GetMetadata (tmpl);
var body = Render.StringToString (templateContent, new { name = "John Doe" });
var from = metadata["from"].FirstOrDefault();
var to = "johndoe@mywebsite.org";
var subject = metadata["subject"].FirstOrDefault();
	using System.Linq;
	using Nustache.Core;

	static ILookup<string, string> GetMetadata(string templateContent) {
	// All metadata are written as {{! key: value }}. {{! ... }} is a comment in Mustache.
	// This function uses the possibility to alter start and end delimiters to scan for {{! }}
	// instead of {{ }}. With {{! as start delimiter, {{!! becomes a comment. I don't think
	// you need comments in this case, but I think this is a neat way to include metadata in
	// the templates.
	return new Scanner("{{!", "}}")
	.Scan (templateContent)
	.OfType<VariableReference> ()
	.Select (varRef => varRef.Path.Split(':'))
	.Where (x => x.Length == 2)
	.ToLookup(x => x[0].Trim(), x => x[1].Trim());
	}

	/*
	Usage
	=====

	template:
	{{! from: admin@mywebsite.org }}
	{{! subject: Regarding your browser history }}
	<body>
	<h1>Dear {{ name }}</h1>
	<p>.....</p>
	</body>
	*/

	var tmpl = "{{! from: admin@mywebsite.org }}\n {{! subject: Regarding your browser history }}\n <body>\n <h1>Dear {{ name }}</h1>\n <p>.....</p>\n </body>";
	var metadata = GetMetadata (tmpl);
	var body = Render.StringToString (templateContent, new { name = "John Doe" });
	var from = metadata["from"].FirstOrDefault();
	var to = "johndoe@mywebsite.org";
	var subject = metadata["subject"].FirstOrDefault();