set-tabs in text%

Sets the tabbing array for the editor.

Setting tabs is disallowed when the editor is internally locked for reflowing (see also Locks).

• (send a-text set-tabs tabs tab-width in-units?) -> void
     tabs : list of real numbers
     tab-width = 20 : real number
     in-units? = #t : boolean

  The tabs list determines the tabbing array. The tabbing array specifies the x-locations where each tab occurs. Tabs beyond the last specified tab are separated by a fixed amount tab-width. If in-units? is not #f, then tabs are specified in canvas units; otherwise, they are specified as a number of spaces. (If tabs are specified in spaces, then the graphic tab positions will change with the font used for the tab.)