type normal
var option of integer
var flag of flags wxEXPAND,wxALL,wxLEFT,wxRIGHT,wxTOP,wxBOTTOM,wxALIGN_CENTER,wxALIGN_LEFT,wxALIGN_TOP,wxALIGN_RIGHT,wxALIGN_BOTTOM,wxALIGN_CENTER_HORIZONTAL,wxALIGN_CENTER_VERTICAL,wxNORTH,wxSOUTH,wxEAST,wxWEST,wxGROW,wxSHAPED,wxSTRETCH_NOT
-var border of integer
+var border of dimension
var size of coord
derived from sizer_item