Add support for calculations

[rymohr]

Need to be able to write something like this:

template = "{{followers/following}}"
context = {followers: 97, following: 14}

Handlebars.compile(template)(context) # => "6.9"

[jeffmohr]

Sweet! What about things like degree (in-degree, out-degree, or plain degree). Special case for those or that actually lands in the metrics engine?

[rymohr]

I think I'd prefer to keep metric specific logic out of the templating engine. If the metric is available on the entity it could be used just like any other attribute though.

Basic idea would be that any time metrics were updated it would cache the value on the entity itself.

Only concern is possible conflicts with other attributes (very likely that degree will be used to track college degree). One option is just to append "centrality" to all the metrics.

element.get('degreeCentrality')

Other option is to just namespace the metrics to differentiate them from the actual account attributes:

element.get('metric:degree')

Preferences?

[jeffmohr]

I prefer the metric approach over adding centrality to it so we have a bit more flexibility about what people are calculating using metrics.