Re: Polysemy in programming langs (was: Why does the meaning of words change?)

Ray Brown wrote:
>
> On Saturday, April 17, 2004, at 09:26 PM, Philippe Caquant wrote:
>
> > The same with instructions like: A = B, which in
> > reality mean "copy B to A".
>
> Yep - copying the value of location B into location A is, of course, what
> goes on in the computer & is probably how one would think of it at a low
> level; in high level programming it's rather:
> "variable A is assigned the value of variable B."

Then there was the PDP-8, the first mini-computer IIRC,
introduced in the 1960s. The only way to store the value
of the accumulator into memory was via the instruction
DCA, Deposit and Clear Accumulator. This copied the
value to memory then set the accumulator to zero.

(The PDP-8 used 4K of 12-bit words.)

--Ph. D.

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