I did not take it to mean dimension as in |<---- number ---->| (extension lines, dimension lines and value) ie as in a dimension object, … I took the OP to mean measurements of primitives.
SketchUp can change some geometric objects via the fields in Entity Info (called “Properties” in most CAD applications.)
SketchUp also has axial constraints and a perpendicular constraint (via arrow keys).
But Mike was right. To use SketchUp one must put away all the old CAD ways, and learn the “UNCAD” way of SketchUp.
(If you take the time to actually READ SketchUp’s U.S. patent, it will become clear that the originators purposely designed SketchUp’s interface to NOT be like all the other CAD applications.)
So okay anyway, I’ll entertain a thread on the possibility of writing a plugin / extension to give SketchUp a more CAD-like interface (regardless of whether it be economical or would be in demand.)