implement block.alias, so consecutive each-blocks dont get i, i_1, i_2...

src/generators/Generator.js

@@ -40,7 +40,7 @@ export default class Generator {
 		// allow compiler to deconflict user's `import { get } from 'whatever'` and
 		// Svelte's builtin `import { get, ... } from 'svelte/shared.js'`;
 		this.importedNames = new Set();
-		this._aliases = new Map();
+		this.aliases = new Map();
 		this._usedNames = new Set( [ name ] );
 	}
 
@@ -54,12 +54,11 @@ export default class Generator {
 	}
 
 	alias ( name ) {
-		if ( this._aliases.has( name ) ) {
-			return this._aliases.get( name );
+		if ( !this.aliases.has( name ) ) {
+			this.aliases.set( name, this.getUniqueName( name ) );
 		}
-		const alias = this.getUniqueName( name );
-		this._aliases.set( name, alias );
-		return alias;
+
+		return this.aliases.get( name );
 	}
 
 	contextualise ( block, expression, context, isEventHandler ) {

src/generators/dom/Block.js

@@ -29,6 +29,7 @@ export default class Block {
 			destroy: new CodeBuilder()
 		};
 
+		this.aliases = new Map();
 		this.getUniqueName = this.generator.getUniqueNameMaker( options.params );
 
 		// unique names
@@ -61,6 +62,14 @@ export default class Block {
 		}
 	}
 
+	alias ( name ) {
+		if ( !this.aliases.has( name ) ) {
+			this.aliases.set( name, this.getUniqueName( name ) );
+		}
+
+		return this.aliases.get( name );
+	}
+
 	child ( options ) {
 		return new Block( Object.assign( {}, this, options, { parent: this } ) );
 	}

src/generators/dom/visitors/EachBlock.js

@@ -7,7 +7,7 @@ export default function visitEachBlock ( generator, block, state, node ) {
 	const create_each_block = node._block.name;
 	const each_block_value = node._block.listName;
 	const iterations = block.getUniqueName( `${each_block}_iterations` );
-	const i = block.getUniqueName( `i` );
+	const i = block.alias( `i` );
 	const params = block.params.join( ', ' );
 	const anchor = block.getUniqueName( `${each_block}_anchor` );