About an Incremental Mapkey
You can record an incremental mapkey by setting the relation_text_trail_output configuration option to yes and the relation_tool_mapkey_behavior configuration option to increment. You can record and run an incremental mapkey in the Relations dialog box only.
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You cannot record an incremental mapkey if you have set the relation_text_trail_output configuration option to no even if the relation_tool_mapkey_behavior configuration option is set to increment. However, you can run a mapkey that was recorded earlier with the relation_text_trail_output configuration option set to yes regardless of this option’s setting when you run the mapkey.
The incremental mapkey records the insertion point in the Relations dialog box. The incremental mapkey records only the newly added text or action performed at the insertion point. When you run the recorded mapkey, it performs the recorded operations starting at the recorded insertion point. It adds or removes text incrementally to the current text set in the text area. The incremental mapkey does not delete or replace the pre-existing text or relation sets if it is not defined to do so.
With an incremental mapkey you can:
Add text and relation sets in the Relations dialog box by running the mapkey again at the required insertion point. You may add multiple lines of text at the same time.
Replace text with new text. You can select text and run the mapkey again to replace the selected text with the new text in the existing text set.
Delete a specific portion of the text from a relation set in the Relations dialog box. You can delete the number of characters before or after that current cursor position as recorded in the mapkey.