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ON

Keyword Abbreviation Token (hex) Version(s) Classification
ON none 91 1.0+ Preposition

Syntax  
[ ON selector ] { GOSUB | GOTO } lineNumber [ , lineNumber ] ...
 ~ or ~
KEY [ { ON | OFF | key_number [ , definition ] } ]
 ~ or ~
{ APPEND | BACKUP | BOOT | BLOAD | BSAVE | CATALOG | COLLECT | CONCAT | COPY | DIRECTORY | DLOAD | DSAVE | DVERIFY | HEADER RENAME | RUN | SCRATCH } [ parameter ]... [ { , | ON } U device_number ] [ parameter ]...
 
 
Purpose  
Influence the behavior of other statements/commands.

 
 
Remarks  
The use of ON/OFF with the KEY command seems to be from the unreleased Commodore LCD.  Remnants of this code can be found in the BASIC 7.0 ROMs of the Commodore 128; however it doesn't function in v7.0 and will generate SYNTAX ERROR. 
 
Example:
10 INPUT N
20 ON N GOTO 100, 200, 300
30 STOP
100 PRINT 1 : END
200 PRINT 2 : END
300 PRINT 3 : END
 
With the disk-related commands (DLOAD and friends), the ON preposition appears to perform the same task as a comma: to seperate items in a list.  However the ON keyword may be used where a comma would generate a SYNTAX ERROR.  Very hard to describe, so here are some examples!
DIRECTORY "*" , U8
0 "SAMPLE DISK     " H2 2A
664 BLOCKS FREE

READY.
DIRECTORY "*" ON U8
0 "SAMPLE DISK     " H2 2A
664 BLOCKS FREE

READY.
DIRECTORY , U8

?SYNTAX ERROR
READY.
DIRECTORY ON U8
0 "SAMPLE DISK     " H2 2A
664 BLOCKS FREE

READY.
 
Compare With  
 
Contrast With  
OFF 
 
See Also  

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