Handling selectable repeat separators

Some repeatable items in the SELECT statement syntax have a repeat separator that you can select (rather than a constant such as a comma). For example, the expression clause as shown in Example of a selectable repeat separator uses an operator (oper) as a repeat separator.
Figure 1. Example of a selectable repeat separator
  Process   Options   Utilities   Help
 ──────────────────────────────────────────────────────────────────────────────
 FM/Db2 (DFG2)            Advanced SELECT Prototyping

 Prototyping: expression clause                    Status: clause incomplete

  ◄─ oper ──────────────────────────┐
 ───┬─────┬─┬─ function ──────────┬─┴─
    ├─ + ─┤ ├─(─ expression ─)────┤
    └─ - ─┘ ├─ constant ──────────┤
            ├─ column ────────────┤
            ├─ hostvar ───────────┤
            ├─ register ──────────┤
            ├─(─ scalarfullsel ─)─┤
            ├─ duration ──────────┤
            ├─ caseexpr ──────────┤
            ├─ castspec ──────────┤
            └─ sequenceref ───────┘

 SELECT ALL




 Command ===> _____________________________________________________ Scroll PAGE
  F1=Help      F2=Split     F3=Exit      F4=Deselect  F5=InsRpt    F6=Executed
  F7=Backward  F8=Forward   F9=Swap     F10=PrvRpt   F11=NxtRpt   F12=Cancel
To show how to handle selectable repeat separators, we'll use an example. To generate the following expression clause:
AMT1 + AMT2 - AMT3
where the columns AMT1, AMT2, and AMT3 are three repeat items, and + and - are the two repeat separators, perform the following steps:
  1. Move the cursor to the column element and press Enter. A pop-up panel is displayed.
  2. Type AMT1 and press the InsRpt function key (F5). AMT1 is added to the clause:
    AMT1
  3. Move the cursor to the oper repeat separator and press the InsRpt function key (F5). A list of valid repeat separators is displayed.
  4. Move the cursor to the + repeat separator and press Enter. + is added to the clause:
    AMT1 +
  5. Press the Exit function key (F3). The syntax for the expression clause is redisplayed.
  6. Move the cursor to the column element and press Enter. A pop-up panel is displayed.
  7. Type AMT2 and press the InsRpt function key (F5). AMT2 is added to the clause:
    AMT1 + AMT2
  8. Move the cursor to the oper repeat separator and press the InsRpt function key (F5). A list of valid repeat separators is displayed.
  9. Move the cursor to the - repeat separator and press Enter. - is added to the clause:
    AMT1 + AMT2 -
  10. Press the Exit function key (F3). The syntax for the expression clause is redisplayed.
  11. Move the cursor to the column element and press Enter. A pop-up panel is displayed.
  12. Type AMT3 and press the InsRpt function key (F5). AMT3 is added to the clause:
    AMT1 + AMT2 - AMT3
Note: The repeat separator is associated with the repeat item it follows. When the last repeat item is current, you cannot edit the repeat separator.