| Allegro CL version 8.2This page is new in 8.2. |

**Arguments: ***
x y end1-x end1-y end2-x end2-y *&key (*margin* 4)*
*

Returns true if a point lies on (or nearly on) a line segment amd
returns `nil`

otherwise.

The first two arguments are real numbers for the X and Y coordinates of the point, and the remaining required arguments are real numbers for the endpoints of the line segment.

The ** margin** argument is a real number
indicating the distance from the line within which the point must lie
to be considered on the line. If it is within this distance, then true
is returned, and otherwise

`nil`

is returned.
See also **on-line-segment-p**.

Copyright (c) 1998-2015, Franz Inc. Oakland, CA., USA. All rights reserved.

Documentation for Allegro CL version 8.2. This page is new in the 8.2 release.

Created 2010.1.21.

| Allegro CL version 8.2This page is new in 8.2. |