Asteroid Shower

[SMcNeill]

For any IF statement, it's always implied <> 0 for a truth expression.

IF holdspace THEN ...  

The above is the exact same as if you had typed IF holdspace <>  0 THEN ...

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IF _KEYDOWN(32) = 0 AND holdspace THEN holdspace = 0

The above *should be* the same as typing IF _KEYDOWN(32) = 0 AND holdspace <> 0 THEN holdspace = 0.

The reason I say *should* is that sometimes those types of statements can get resolved in an unexpected order such as IF _KEYDOWN(32) = (0 AND holdspace) THEN....   If I was writing that line of code, I think I'd either write it as:

IF NOT _KEYDOWN(32) AND holdspace THEN holdspace = 0

Or, perhaps as:

IF (_KEYDOWN(32) = 0) AND (holdspace <> 0) THEN holdspace = 0

I'm a strong believer in taking the ambiguity out of any order of operations.  As written, I'd personally question if it's doing exactly what I'd be expecting it to do for me. 

[aurel]

The above *should be* the same as typing IF _KEYDOWN(32) = 0 AND holdspace <> 0 THEN holdspace = 0.

Thanks Steve ..i was asking just about that , because some other dialects use as -1 as TRUE
or some use 1 or as you said everything that not NULL as TRUE

[TempodiBasic]

@mnrvovrfc
It is fun!
Why do you not use sounds?

Nevertheless it works better on my notebook adding at line 83 (before the last LOOP) this code

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    _Limit 10

Is it normal that when I gain the rigth edge, the astroship appears again on the left edge?

[bplus]

2 If holdspace <> 0 then make holdspace = 0