NXC: concatening assignments with arrays: error!

[HaWe]

if I write

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buf=sum[j]=sum[j] + d2;

I get a compiler error (";" expected")

but this works:

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sum[j]=sum[j] + d2;
buf=sum[j];

[muntoo]

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buf=sum[j]=sum[j] + d2;

NXC doesn't support that yet.

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int line = 8;
for(int lol; lol = line; line--)
{
    TextOut(0, line*8, "lol", 0);
}

Will probably give you an error, for example.

[HaWe]

I think you're wrong, muntoo.
It's legal C code, and NXC should indeed support that too.
Already since the falsly as "obsfucated" decried chess program, IIRC.
;)
this should work also:

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buf=sum[j]+=d2;

[muntoo]

It's legal C code, and NXC should indeed support that too.

I meant that NXC doesn't support it yet. I have nothing against ACDC.
Of course, I do have something against obfuscation (unless I'm trying to write obfuscated code on purpose).

[HaWe]

no muntoo, it normally should.
The reason why I posted it of course is that I observed that it actually doesn't. Why else should I post it? it's a bug!
Your postings really don't help along.
What's that all about "obsfucation" with this issue? It's a simple right-to-left concatening of assignments!

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e=d=c=b=a;
a=(a>b?)c:d;
a=b=a>d;
a=(c<<d>>e);

On the other hand, this works fine:

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p=t=0;
SoundRecord[t]=SoundLevel=SensorValue(S2);

but NOT this:

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buf=sum[j]=sum[j] + d2;
buf=sum[j] += d2

why?
I guess it's an issue related to temp variables used for array types.

[spillerrec]

NXC does indeed support chained assignments, but as shown it appears it cannot understand the syntax correctly when arrays are included.

[HaWe]

right, spiller, but why else do you think I posted this bug? ;)
look at my example of an another chained assignment with arrays, but that works fine:

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SoundRecord[t]=SoundLevel=SensorValue(S2);

I guess it's because of temporary vars internally used for calculating this part:

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array[x]=array[x]+d
array[x]+=d

and again:
it's a syntax error (parser or pre processor), not a run time error!

[muntoo]

OK, I get it now.

[spillerrec]

Helmut, the post was intended to muntoo, I didn't notice that you had explained it that clearly already.

I don't think it is related to temporary variables because this (which does not need any temporary variables) does not work either:

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bla = bla2[1] = bla3;

But mostly because of the type of error message. It thinks the code is wrong (though it isn't) and therefore doesn't even attempt to compile it. (When it cannot compile it correctly it usually ends up being some gibberish together with some NBC code. (Or doesn't even notice it as seen several times ; ) ))

[afanofosc]

Once upon a time NXC did not allow an assignment to be an expression (i.e., something that returns a value that could then be used by something else). Now it does in a lot of cases but not all cases. I probably will not spend a lot of time perfecting this since there are many, many, many, many ways you can work around this compiler limitation. Ditto for when += does or does not work. If you want to use a real C compiler you could try NXTOSEK. Before I get around to these kind of problems I will probably get around to implementing API functions for the Tetrix controllers. Please do not start holding your breath but if you have already started you should exhale and breathe normally!

John Hansen