A selection is a set of ranges (to support discontinuous selection, for
example when selecting a column in a matrix).
If there is a single range and that range is collapsed, the selection is
collapsed.
A selection can also have a direction. While many operations are insensitive
to the direction, a few are. For example, when selecting a fragment of an
expression from left to right, the direction of this range will be "forward".
Pressing the left arrow key will sets the insertion at the start of the range.
Conversely, if the selection is made from right to left, the direction is
"backward" and pressing the left arrow key will set the insertion point at
the end of the range.
A selection is a set of ranges (to support discontinuous selection, for example when selecting a column in a matrix).
If there is a single range and that range is collapsed, the selection is collapsed.
A selection can also have a direction. While many operations are insensitive to the direction, a few are. For example, when selecting a fragment of an expression from left to right, the direction of this range will be "forward". Pressing the left arrow key will sets the insertion at the start of the range. Conversely, if the selection is made from right to left, the direction is "backward" and pressing the left arrow key will set the insertion point at the end of the range.
See Also
Range]]