Grab Copy Demo from Tek1 on Vimeo.

Dimension Panels Command - With Jig from Tek1 on Vimeo.

The following are some principles essential for the success of any venture. They are commonsensical, but perhaps counter-intuitive.

This is best illustrated by example:

The notoriously detailed AutoCAD .net documentation strikes again! What exactly is meant by a collinear LineSegment2d? Who knows? Luckily the documentation is there to save the day:

Place Section Commands from Tek1 on Vimeo.

Here is the relevant GitHub issue. They were so sneaky. The posted a ruby gem, but with some sneaky additions. This was not posted on Github. They were hoping that nobody would notice. But someone did. In order to pull this off, you’d have to be a fairly sophisticated rubyist, with a good understanding of rack, and some basic security knowledge exploits. They must have some time on their hands to pursue such nefarious ends.

If you want a comprehensive tutorial, then perhaps consider getting Metaprogramming by Perotta. A huge proportion of the notes here are derived from Perotta.