> -----Original Message-----
> From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu] On
Behalf
> Of Vitaliy
> Sent: 26 February 2010 09:25
> To: Microcontroller discussion list - Public.
> Subject: Re: [PIC]Function declaration causes error in one
> programbutnotanother
> 
> Alan B. Pearce wrote:
> >> The 'for' construct is much more concise, elegant
> >> and easier to understand.
> >
> > ;))) Not according to Chuck Hellebuyuk that wrote "Beginners Guide
to
> > Embedded C Programming" (available through Microchip). He also
doesn't
> > like
> > the ++ and += styles of notation ...
> 
> You know, I use the ++ notation myself, but I choose not to use the +=
> style
> notation, because in my mind it's a C-ism that makes the code less
> readable
> while offering no real benefit. Maybe it made sense when screens were
80
> characters wide?
> 
> Vitaliy

It makes sense to me in the context of a mid-level language; in
assembler an add instruction will typically add the value of one
register to an accumulator or another register and that's the entire
operation

e.g.

    movf b,W
    addwf a,F

which is nicely equivalent to:

    a += b;


The long hand expression implies two distinct operations i.e. the
addition itself and the moving of the result:

    a = b + c

    movf b,W
    addwf c,W
    movwf a

The move is clearly redundant when the result is stored in one of the
original operands, and obviously no modern compiler worthy of
consideration would actually include a redundant move.  However I'm
wondering if this was helpful for early compilers, i.e. that operation
would produce more efficient code without using an optimiser?

Regards

Mike

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