"Sample Edge" node

Just like the "Sample Curve" node, this node would take for input a mesh and an index (or two indexes, the first vertex's and second vertex's, if edge index is not on the table) and return the direction, angle and length of the edge at that index.

Direction and Length would be easy to implement (simply get the distance between vertices or subtract one another), and Angle would return the angle the face users of that edge meet. (If the edge has less than two or more than three face users, return zero or another arbitrary value)

It'd be very useful to implement angle-based masking, especially Auto Smooth.

Here's a mockup of the node :