Anchor
Connects two or more separate objects, connected at their endpoints, into a single-object polyline. Objects that overlap cannot be joined.
Note: If you want to create a polyline from a partial chain of segments, or if you have overlapping objects, see Chain Polyline.
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The objects now comprise one object, as you can see in Select mode. 
You can also first select the objects, then activate Join Polyline and immediately select Finish. Local menu options: Delete Original Objects: Removes the original segments, leaving only the polyline. 
AuAnchor 1112 1112 to Auto joining: Automatically selects all objects connected to the selected object. This option must be active before selecting any segments. You can select any object in the chain, not only the first or last object. If more than one segment branches from an endpoint, the chain will stop. 
Anchor
