Replace *variable and %special with scope

[justinbmeyer]

Note: A discussion of this topic can be found on youtube.

This issue represents a combination of several other issues with the goal of cleaning up some of the uglier, less "handlebars" and "javascript" bits of can-stache.

• move any non-contextual access or mutations to a reserved scope variable
• make #with and #each use hash params

Move non-contextual access to a reserved scope variable

*variable => scope.var.variable

Move access to template variables (references scope) to scope.var.. Examples:

<can-import from="date-helpers" value:to="*dateHelpers"/>
{{*dateHelpers.prettyDate( date )}}
=>
<can-import from="date-helpers" value:to="scope.var.dateHelpers"/>
{{scope.var.dateHelpers.prettyDate( date )}}

%special => scope.special

Allow special keys to be looked up directly on scope. Examples:

{{#each items}} {{%index}} {{/each}}
=>
{{#each items}} {{scope.index}} {{/each}}

<div on:click="doSomething( %element, %event, %arguments )"/>
=>
<div on:click="doSomething( scope.element, scope.event, scope.arguments )"/>

Access to other values:

• Helpers passed to the template scope.helpers.helperName
• Partials passed to the template scope.partials.partialName
• Tags passed to the template scope.tags.component-name
• <can-template name="NAME">s passed to the template scope.templates.NAME
• Inline partials created in the template scope.partials.partialName
• The current renderer scope.view

Implementation Details

1. Each template has a references scope, this should be expanded to be a special object that looks like: {vars: {}, helpers: {}, partials: {}, templates: {}, view: renderer, optionsScope: optionsScope}. This object should be the templateContext.

• When a partial is looked up on the templateContext, it should look in its partials, and then explore the optionsScope.
• When a helper is looked up, it should look in its helpers, and then explore the options scope, and then the registered helpers.

2. scope[can.getKeyValue] needs special rules. It probably should first look up in the references scope, then in the "notContext" contexts, then in the normal contexts.
3. In 4.0, I would like to change the use of the options arg to renderers template(data, options) to essentially set the templateContext.

• I'd also like to think about special events being registered. <can-import from="drag-drop" value:merge-to="scope.events"/>

make #with and #each use hash params

• - {{#with firstName=person.first}}
• - {{#each items item=value num=index}}

[phillipskevin]

This is done in major.