path metaphor

Two places and something between them. Bridge, road, crossing, tunnel, fork. You pour a sequence or a transition into it, with the start on one side, the end on the other, and the hard middle drawn as a gap or a span. This is the class for anything shaped like getting from here to there. What it adds for free is engineering. A bridge implies someone designed it, tested it, and that it holds, which is exactly the assurance most transitions do not have.

Two places and something between them. Bridge, road, crossing, tunnel, fork. You pour a sequence or a transition into it, with the start on one side, the end on the other, and the hard middle drawn as a gap or a span. This is the class for anything shaped like getting from here to there. What it adds for free is engineering. A bridge implies someone designed it, tested it, and that it holds, which is exactly the assurance most transitions do not have.

Example

Best when the content is a move from one state to another and the interesting part is the middle.