the design of a gap buffer should follow the typical behavior when editing text. Editing text has two parts: modifying it and simply browsing it. The text contains a 'cursor', which indicates the actual position. When in editing mode, we have to take care to use smart memory management. For this purpose we introduce a little memory gap into the string where new characters can be inserted, so not on every insert() all the following characters have to be moved a gap buffer is layed out like this: |***********************..........**********| ^ ^ ^ ^ begin() gbegin() gend() end() the following (in)equalities should always hold: gend() > gbegin() gend() - gbegin() <= gmaxsize() end() >= gend()

these are methods to control the cursor position. This is a long description for this group, but it will only be displayed if any of its contents has a long description. Hmm, but then the group is a child of its own section so thats okay! { Group1 move the cursor one position forward

move the cursor one position back

shift the cursor d positions

return the current position

set the current position

} Insert an item