Chapter 31 Line Edit Mode - Radio Shack TRS-80 Model 4 Owner's Manual

Chapter 3/ Line Edit Mode
This mode enables you to "debug" (correct) programs quickly and
efficiently. It allows you to correct a program line without having to
re-type the entire line.
If your computer encounters a syntax error while executing a
program, it automatically puts you in the "line edit mode." The display
shows:
Syntax error in line nUMber
Re ach'
line nUfTlber
(line number is the program line in which the error occurred.) In this
case, you are ready to use the edit mode commands and
subcommands described later in this Chapter.
However, if you wish to activate the line editor yourself (because you
have noticed a mistake or wish to make a change in a long program
line), type:
EDIT
1
ine nUfTlbe r
(ENTER)
This lets you edit the specified line number. (If the line number you
specify has not been used, an "Undefined line number" error occurs.
If you do not have a space after the word EDIT, a "Syntax error"
occurs.)
You may also type:
ED IT.
(ENTER)
The period after EDIT means that you want to edit the current
program line, the last line entered, the last line altered, or a line in
which an error has occurred. Notice that you need to type a blank
before the period; otherwise, BASIC gives you a "Syntax error"
message.
For example, type the following line and press (ENTER). (To type the
exponent sign ", press (CLEAR)C]).
100 FOR 1= 1 TO 10 STEP .5: PRINT It I"2t 1"3:
NE)-(T
This line will be used in exercising all the edit subcommands
described below.
Now type EDIT 100 and press (ENTER). The computer displays:
100
This starts the editor. You may now begin editing line 100.
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