string slicing using len()

[programandala.net]

I didn't understand why a piece of my program didn't work as expected. I suspected something was wrong with the for-next loop. I tried some tests, simplified versions of the problem, and finally find out the following:

Code:

dim text as string dim i as ubyte let text="hello world!" cls print "Fine:" for i = 0 to len(text)-1 print i,text(to i) next i pause 0 cls print "All texts are complete!:" for i = 0 to len(text)-1 print i,; let text = text(to len(text)-1) print text next i stop

It was a surprise. The second loop prints the same original text every time.

I tried the equivalent code in Sinclair Basic, and of course it worked as expected:

Code:

10 LET A$="hello world!" 20 FOR I=0 TO LEN(A$)-1 30 PRINT I,; 40 LET A$=A$(TO LEN(A$)-1) 50 PRINT A$ 60 NEXT I 70 STOP

Then I tried it without the loop:

Code:

dim text as string let text="hello world!" cls print text let text = text(to len(text)-1) print text let text = text(to len(text)-1) print text let text = text(to len(text)-1) print text let text = text(to len(text)-1) print text let text = text(to len(text)-1) print text let text = text(to len(text)-1) print text let text = text(to len(text)-1) print text stop

And the problem remained.
Then I hardcoded some slicing values:

Code:

dim text as string let text="hello world!" print text let text = text(to 10) print text let text = text(to 9) print text let text = text(to 8) print text let text = text(to 7) print text let text = text(to 6) print text let text = text(to 5) print text stop

And it worked fine.

Is there something I'm missing in my code or is it a compiler issue?