implement this.redirect in preload (#83)

src/core/create_template.ts

@@ -34,59 +34,6 @@ export default function create_templates() {
 			return template.replace(/%sapper\.(\w+)%/g, (match, key) => {
 				return key in data ? data[key] : '';
 			});
-		},
-		stream: (req: any, res: any, data: Record<string, string | Promise<string>>) => {
-			let i = 0;
-
-			let body = '';
-
-			function stream_inner(): Promise<void> {
-				if (i >= template.length) {
-					return;
-				}
-
-				const start = template.indexOf('%sapper', i);
-
-				if (start === -1) {
-					const chunk = template.slice(i);
-					body += chunk;
-					res.end(chunk);
-
-					if (process.send) {
-						process.send({
-							__sapper__: true,
-							url: req.url,
-							method: req.method,
-							type: 'text/html',
-							body
-						});
-					}
-
-					return;
-				}
-
-				const chunk = template.slice(i, start);
-				body += chunk;
-				res.write(chunk);
-
-				const end = template.indexOf('%', start + 1);
-				if (end === -1) {
-					throw new Error(`Bad template`); // TODO validate ahead of time
-				}
-
-				const tag = template.slice(start + 1, end);
-				const match = /sapper\.(\w+)/.exec(tag);
-				if (!match || !(match[1] in data)) throw new Error(`Bad template`); // TODO ditto
-
-				return Promise.resolve(data[match[1]]).then(chunk => {
-					body += chunk;
-					res.write(chunk);
-					i = end + 1;
-					return stream_inner();
-				});
-			}
-
-			return Promise.resolve().then(stream_inner);
 		}
 	};
 }