Working with clip paths

[john-clarke]

I've tried to replicate this simple example http://bl.ocks.org/mbostock/4062844 which uses clipPaths to format line segments. But I'm running into trouble figuring out how to do the chaining properly in d3.chart. I think the issue might have to do with the datum(data) instruction and/or the fact that the series line is actually rendered twice.

The end goal is to render the following chart https://resources.cisnet.cancer.gov/projects/#shg/tce/current-prevalence/opts/mode=period-cohort;interval=5;show_all_series=true;real_series=1890;show_reference=false;reference_series=1890;sex=male;render_method=chart;advanced=true;show_reference=false using clipPaths so that I can re-introduce D3 transitions. Currently, they don't transition well because the series line is actually rendered as two segments using the defined() method.

Any hints would be appreciated.