The Question of Braces in APLASCII 4366

TaliesinSoft

You are quite right. This page was written some time ago, and I carelessly included some buttumptions I had then made; I was tardy in correcting it, but have done so now.

When I first saw a Tektronix 4014 with those new characters, I just buttumed that the one manufacturer just picked some new characters, and, *boom*, there was a de-facto standard.

A dollar sign that *looks* like an overstrike of an S with a vertical bar; the left and right tack, and the curly braces because ASCII happens to have them - I'm sorry to say this, but at the time, it seemed to me that the choices weren't made with *terribly* much thought.

I could see how being able to print a dollar sign in APL might extend APL to other areas of applicability. But if so, why not make a good-looking dollar sign - and let the inferior subsbreastute be used on 88-character terminals?

As for the other characters - except for diamond, they never *did* get used in APL implementations. Would they have been likely to?

A radical symbol (for square root and n-th root) and an angle symbol (for A angle B producing a result similar to ATAN2(A,B) in FORTRAN) would have been two very obvious things to add to APL.

A raised null, for a unary operator that multiplies its argument by pi-180, might have been another one to consider. (But the circle already multiplied by pi, of course.)

Thus, one manufacturer's whim, and not a solemn standardization effort, was what came to mind. IBM, with its APL keyboards using the three extra keys for the extra APL2 overstrikes only, has, as might be expected, dismissed them with contempt, unfortunate as that may be.

I think it is unfortunate that APL has failed to be as much of a continuing presence in the world of computing as I would like. Of course, what I would like is this...

You go to the store, and buy an IBM personal computer.

The keyboard comes with APL symbols on the front of the keys - and some extra characters on the tops of the keys as well. Its layout otherwise resembles a standard 101-key keyboard.

The file system treats files as lists of records whose length is separately indicated. Although control characters are used with some types of external printers, internally in disk files and on the display, there are just 256 printable characters. Control functions are indicated through other means.

The computer comes with a FORTRAN compiler, as well as compilers for Pascal, Algol 60, Algol 68, and interpreters for BASIC and APL.

There's also a graphical user interface that can be invoked through a command. A set of subroutine calls is provided in the operating system to draw windows, buttociate subroutines with menu selections, and so on, making it easy for programmers to add GUI support to existing programs (no Macintosh-style event loop). Other than that, the GUI resembles Windows 3.1 in its general appearance.

Of course, the processor supports the Motorola 68020-68882 architecture. When 64-bit support was added, however, it was decided that instead of simply extending the existing ISA, as incompatibility would exist anyways, the 64-bit mode would conform to an architecture for which a pool of software already existed - and which used the same big-endian data formats as the 68000 line. So it flips into z-Architecture mode to handle 64 bits.

Now, *that* would be a computer.

John Savard