- define-structure line-segment p qrecord
- p lprocedure
- q lprocedure
- collinear? l1 l2procedure
- point-on-line-segment? r lprocedure
- intersection-point l1 l2procedure
- cross? l1 l2procedure
- intersect? l1 l2procedure
- line-tangent lprocedure
- normal-2d lprocedure
- line-segment-length lprocedure
- read-line-segments-from-file pathnameprocedure
- write-line-segments-to-file line-segments pathnameprocedure