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BASIC keyword
Keyword:	NEXT
Abbreviation:	N Shift+E
Type:	Command
Token code:	-/$-
Handling routine in BASIC ROM:	-–- $-–-
List of all BASIC keywords

Remark: This article describes the BASIC-Command NEXT in BASIC V2 at the Commodore 64.

Typ: Command
General Programming-Syntax: NEXT [<Variable>],[<Variable>]…

The BASIC-Command NEXT must be using with the BASIC-Command FOR. NEXT is the end of a FOR…TO…STEP…NEXT-loop. The declaration of the loop-variable by NEXT isn't as may be necessary. For every opened loop with FOR must be used the close-command NEXT.

By using NEXT without FOR the BASIC-error ?NEXT WITHOUT FOR  ERROR IN line appears. The maximum of open FOR-Loops are 9, by opening the 10th FOR-loop the BASIC-error ?OUT OF MEMORY  ERROR IN line is viewing.

When the BASIC-Command RUN is executed, the counter of the FOR-Loop is incremented (1 rising up without using the BASIC-Command STEP). A FOR-Loop will be finished, when the counter in the term is true

FOR…NEXT-loops din't interlaced, because by to many opened FOR-loops occured a BASIC-error or the programmer is amazed about something.

[edit] Examples

10 FOR X=1 TO 15: PRINT X: NEXT X

Printed the numbers 1 until 15

10 FOR X=1 TO 15: PRINT X: NEXT

The same example, but NEXT without the variable

10 FOR X=1 TO 10
20 FOR Y=1 TO 10: PRINT X*Y;: NEXT: PRINT: NEXT

NEXT without a variable - example of the small multiplication tables

10 REM Colors
20 FOR X=0 TO 255
30 FOR Y=0 TO 255
40 POKE 53280,X: POKE 53281,Y:
50 FOR A=0 TO 150: REM Delay-loop
60 NEXT A,Y,X

Example with 3 Loops

10 FOR A=0 TO 1E17
20 PRINT X;".Loop - a number, please";:INPUT A$
30 X=INT(VAL(A$))
40 IF X=64 THEN X=1E18
50 NEXT

A endless loop, with a trick in line 40 will be ending this loop.