link-to-if component ala rails's link_to_if helper

component.js

import Ember from 'ember';

const {
  Component,
  computed
} = Ember;

const LinkToIfComponent = Component.extend({

  condition: null,

  routeName: computed('params.[]', function() {
    return this.get('params')[0];
  })

});

LinkToIfComponent.reopenClass({

  positionalParams: 'params'

})

export default LinkToIfComponent;

template.hbs

{{#if condition}}
  {{#link-to params=params}}
    {{yield true}}
  {{/link-to}}
{{else}}
  {{yield false}}
{{/if}}

use.hbs

// assuming a route like "route/:foo_id/:bar_id"

{{#link-to-if "route" 1 2 condition=someBool as |linked|}}
  Hello!
  {{#unless linked}}
    Locked!
  {{/unless}}
{{/#link-to}}

// If `someBool` evals to truthy, renders:
// <a href="/route/1/2">Hello!</a>
// otherwise:
// Hello! Locked!