Radio Shack TRS-80 PC-3 Owner's Manual page 111

Examples:
10 "A" REM THIS IS EXISTING PROGRAM
20 FOR T= 1 TO 100
30 LPRINT T
40 NEXT T
(Etc)
BEFORE doing a MERGE of the next program, make any necessary changes to this program.
Then MERGE the next program: MERGE "PROG2" (example)
10 "B" REM THIS IS MERGED PROGRAM
20 INPUT "ENTER DEPRECIATION:" D
30 INPUT "NUMBER OF YEARS: " ; Y
40 . Etc.
Now you may make changes to the above program since it was the last MERGED portion.
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