use the v attribute with sub.right_menu then can access the t variable in the subfunction
str t="A"
str dd=
F
;BEGIN DIALOG
;0 "" 0x90C80AC8 0x0 0 0 224 136 "{t}_Dialog" "4"
;3 Edit 0x54030080 0x200 68 52 96 13 ""
;1 Button 0x54030001 0x4 116 116 48 14 "OK"
;2 Button 0x54030000 0x4 168 116 48 14 "Cancel"
;END DIALOG
;DIALOG EDITOR: "" 0x2040C02 "*" "" "" ""
str controls = "3"
str e3
if(!ShowDialog(dd &sub.DlgProc &controls)) ret
#sub DlgProc
function# hDlg message wParam lParam
sel message
,case WM_INITDIALOG
,SetWindowSubclass(id(3 hDlg) &sub.WndProc_Subclass_Edit 3 0)
,case WM_DESTROY
,case WM_COMMAND goto messages2
ret
;messages2
sel wParam
,case IDOK
,case IDCANCEL
ret 1
#sub WndProc_Subclass_Edit ;;Edit
function# hwnd message wParam lParam uIdSubclass dwRefData
;OutWinMsg message wParam lParam ;;uncomment to see received messages
sel message
,case WM_CONTEXTMENU
,sub.right_menu hwnd
,ret
int R=DefSubclassProc(hwnd message wParam lParam)
sel message
,case WM_NCDESTROY
,RemoveWindowSubclass(hwnd &sub.WndProc_Subclass_Edit uIdSubclass)
ret R
#sub right_menu v
function hwnd
str s=
F
;1 1 {t} test1
;2 2 {t} test2
;3 3 {t} test3
MenuPopup m.AddItems(s)
int i=m.Show
str s1 s2
if(i and m.GetItemText(i s1 s2))
,EditReplaceSel hwnd 0 s2 1|2|4