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Compile error - INKEY$ can't be called in a FOR loop - Printable Version

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Compile error - INKEY$ can't be called in a FOR loop - mathez - 2015-11-19

Hello,

I am using version 1.3.0-s1121, though I've also tried 1.4.0s1967, and have the following simple program:

Code:
10 FOR l = 1 to 30
IF INKEY$ <> "" THEN GOTO 100
NEXT l
GOTO 10
100 PRINT "*"
The compiler gives these errors:
test.bas:6: Syntax Error. Unexpected token 'NEXT' <NEXT>
test.bas:7: Undeclared label "10"

I am a C/C++ programmer, so I might be missing something but looks like if I have INKEY$ in a FOR loop, it doesn't compile. I can remove the GOTO 10 and do a 10: to fix the second error, though that's not very clean syntax with the line number having to be converted to a label.

But, I haven't yet found a workaround for the INKEY$ problem in a FOR loop.

Thanks so much for the help.

Re: Compile error - INKEY$ can't be called in a FOR loop - boriel - 2015-11-22

The problem here is that the IF THEN is now a composed sentence. You must use END IF, to finish it (think of THEN and END IF as { and } in C++).
So your code should be:
Code:
10 FOR l = 1 to 30
IF INKEY$ <> "" THEN GOTO 100: END IF
NEXT l
GOTO 10
100 PRINT "*"
Actually, THEN can be omitted, and you can insert many sentences, each in a new line:
Code:
10 FOR l = 1 to 30
IF INKEY$ <> "" THEN
   REM You can put many sentences here
   GOTO 100
END IF
NEXT l
GOTO 10
100 PRINT "*"
Also, you can use Labels (e.g. MyLabel: ) ending them in with a colon (Smile, instead of line numbers (line numbers are just considered labels here).