Handlebars - partial template not getting the context - handlebars.js

Question

I have pre compiled all my templates into one js file and loaded the js in the page.
I have 3 templates
Template 1 - a.handlebars
<ul>
{{#each this}}
<li class="a">
{{#key}}
{{> b}}
</li>
{{/each}}
</ul>
Template 2 - b.handlebars
<ul>
{{#each this}}
<li class="b">
{{#key}}
{{> c}}
</li>
{{/each}}
</ul>
Template 3 -c.handlebars
<ul>
{{#each this}}
<li class="c">
{{ this }}
</li>
{{/each}}
</ul>
I have the following JS which load data to the template
var menu= {
a1:{
b1:[c1, c2, c3],
b2: [c4, c5, c6]
},
a2:{
b3:[c7, c8],
b4: [c9]
}
};
Handlebars.templates.a(menu);
The first template (a.handlebars) loads a1 and a2. But when the first template loads the partials b.handlebars it fails. I tried to put a log statement to see what is that I am getting for "this". I got 4 spaces and it was of type string.
I do not understand why b.handlebar is getting a string when I thought I will be getting (example for a1)
{
b1:[c1, c2, c3],
b2: [c4, c5, c6]
}
Previously,I did not pre compile the handlebars. I had all the handlebars in my html and compiled it using Handlebars.compile it worked fine. I do not know why the code is failing after per compiling.
Any help is highly appreciated.
I am trying to get his as my final result:
<ul>
<li class="a">a1
<ul>
<li class="b">b1
<ul>
<li class="c">c1</li>
<li class="c">c2</li>
<li class="c">c3</li>
</ul>
</li>
<li class="b">b2
<ul>
<li class="c">c4</li>
<li class="c">c5</li>
<li class="c">c6</li>
</ul>
</li>
<li class="b">b3</li>
</ul>
</li>
<li class="a">a2
<ul>
<li class="b">b3
<ul>
<li class="c">c7</li>
<li class="c">c8</li>
</ul>
</li>
<li class="b">b4
<ul>
<li class="c">c9</li>
</ul>
</li>
</ul>
</li>
</ul>
But I am getting this. Since the b.handlebars is not getting the object data.
<ul>
<li class="a">a1
<ul>
</ul>
</li>
<li class="a">a2
<ul>
</ul>
</li>
</ul>
My apologies for the very lengthy post. I have been trying to find a solution for this for a while now. Again, any help to resolve this issue would be great.
Thanks.

Answer 1

The issue was caused due to compiling the handlebar/template files using grunt.
Command: "grunt handlebars"
Once I compiled the files using handlers itself, the code started working.
Command: handlebars template_files -f output_file
If anyone knows how to make the compiled code work using grunt command I would definitely would like to know. Thanks.