so you're saying that the table in this section is wrong?
http://en.wikipedia.org/wiki/Computer#History_of_computing
if it is and you can back it up, i sugeest you fix wikipedia.
It isn't wrong.
The exact wording from "The First Computers: History and Architectures"
goes:
The instruction most conspicuously absent from the instruction set of the
Z3 is conditional branching. [...] but there is no straightforward way to
implement conditional sequences of instructions. However, we will show
later than conditional branching can be simulated on this machine.
On the other hand, Wikipedia's article on Plankalkuel says:
Plankalkül drew comparisons to APL and relational algebra. It includes
assignment statements, subroutines, conditional statements, iteration,
floating point arithmetic, arrays, hierarchical record structures,
assertions, exception handling, and other advanced features such as
goal-directed execution.
-- <http://en.wikipedia.org/wiki/Plankalkuel>
In other words, both statements are correct. Z3 did not have conditional
branching (given the type of store it used it would be too hard), however
Plankalkuel did provision conditionals, invocation, and subroutines--all
that is necessary to implement conditional branching.
--On Saturday, September 05, 2009 20:17 -0400 erik quanstrom
<quans...@quanstro.net> wrote:
I wasn't, in this case at least, implying something not backed by firm
evidence. Conditional branching embodied in actual computers goes back
to Plankalkuel on Z3. The idea is as early as Babbage. It comes as
natural even to first-timers, following much more difficult conception
of a notion of control flow, that there must be a manner of
conditionally passing it around.
so you're saying that the table in this section is wrong?
http://en.wikipedia.org/wiki/Computer#History_of_computing
if it is and you can back it up, i sugeest you fix wikipedia.
- erik
