[TUHS] Slashes

[TUHS] Slashes

[Doug McIlroy]

If 19961 is the oldest citation the OED can come up with, "slash"
really is a coinage of the computer age. Yet the character had
been in algebra books for centuries. The oral tradition that underlies
eqn would be the authority for a "solid" name. I suspect, though,
that regardless of what the algebra books called it, the name
would be "divided by".

This is sheer hypothesis, but I have always thought that \ got
onto printer chains and type balls as a crude drawing aid. Ditto
for |. Once the characters became available people began to find
uses for them.

[TUHS] Slashes

[John Cowan]

Doug McIlroy scripsit:

> This is sheer hypothesis, but I have always thought that \ got
> onto printer chains and type balls as a crude drawing aid. Ditto
> for |. Once the characters became available people began to find
> uses for them.

<http://www.bobbemer.com/BACSLASH.HTM> tells us that \ was introduced
into ASCII by Bob Bemer in order to make \/ for 'or' and /\ for 'and'
available, primarily for the use of Algol 60.  It had not been available
in any manufacturer's character set before ASCII-63, as far as is known.
Unfortunately, none of the five existing Algol 60 implementations actually
support these sequences.

| was commonplace, however, as it has at least 15 mathematical uses:
see <https://en.wikipedia.org/wiki/Vertical_bar#Mathematics>.
As far as I know, it has always been used as 'or' on computers.

-- 
John Cowan          http://www.ccil.org/~cowan        cowan at ccil.org
If I have seen farther than others, it is because I am surrounded by dwarves.
        --Murray Gell-Mann

[TUHS] Slashes

[Peter Jeremy]

On 2016-Jul-09 11:59:51 -0400, John Cowan <cowan at mercury.ccil.org> wrote:
>| was commonplace, however, as it has at least 15 mathematical uses:
>see <https://en.wikipedia.org/wiki/Vertical_bar#Mathematics>.
>As far as I know, it has always been used as 'or' on computers.

APL uses it for absolute value and modulo.

-- 
Peter Jeremy
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 949 bytes
Desc: not available
URL: <http://minnie.tuhs.org/pipermail/tuhs/attachments/20160711/e5e545fd/attachment.sig>

[TUHS] Slashes

[Nemo]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 2020 bytes --]

On 9 July 2016 at 09:22, Doug McIlroy <doug at cs.dartmouth.edu> wrote:
> If 19961 is the oldest citation the OED can come up with, "slash"
> really is a coinage of the computer age. Yet the character had
> been in algebra books for centuries. The oral tradition that underlies
> eqn would be the authority for a "solid" name. I suspect, though,
> that regardless of what the algebra books called it, the name
> would be "divided by".

Out of curiosity, I consulted Cajori [1].  All sorts of notations were
used to denote division (including reversed letters) in antiquity
although fractions were commonly denoted by numerator above a
separating line and denominator below.  In 1659, Johann Heinrich Rahn
introduced the symbol ÷ (period above and below a minus sign, Unicode
00F7 -- apologies if the symbol does not display) for division, having
been previously used to indicate subtraction.   In 1684, G.W. Liebniz
introduced ':' for division.  Later authors used both solidus and
reverse-solidus to indicate division.  (Frustratingly, Cajori never
gives a name to the symbol '/'.)

Here is the start of Para. 240 (shades of Algol vs C): "There are
perhaps no symbols which are as completely observant of political
boundaries as are ÷ [Unicode 00F7] and : as symbols for division.  The
former belongs to Great Britain, the British dominions, and the United
States.  The latter belongs to Continental Europe and the
Latin-American countries."  In 1923, the US National Committee on
Mathematical Requirements recommended dropping ÷ (Unicode 00F7) in
favour of the symbol '/' (again nameless).

Bemer, an IBM engineer, argued that the Selectric type ball should be
designed to carry 64 characters required for ASCII, rather than the
typewriter standard 44
(http://www-03.ibm.com/ibm/history/ibm100/us/en/icons/selectric).  The
suggestion was dismissed.  Knuth, in his TeXbook, refers to
"non-mathematical slashes" and entries for virgule and solidus say
"See slash".

[1] A History Of Mathematical Notations Vol I

N.

[TUHS] Slashes

[pete]

On 09/07/2016 15:22, Doug McIlroy wrote:
> If 19961 is the oldest citation the OED can come up with, "slash"
> really is a coinage of the computer age. Yet the character had
> been in algebra books for centuries

1961 is about the time I was learning to type (in Britain), and I was 
taught it as "slash".  My mother - who was an excellent professional 
typist but never had any contact with computers - almost always referred 
to '/' as "slash".  The one exception I can recall is in the usage "... 
and/or ..." where it was sometimes spoken as "... and or or ..." 
(though often the first "or" was simply omitted).

-- 
Pete
Pete Turnbull

[TUHS] Slashes

[Doug McIlroy]

> As far as I know, it [|] has always been used as 'or' on computers.

I was on the NPL (eventually PL/I) committee when IBM 'generously'
increased the 360 character set from 48 to 60. George Radin grabbed
| for OR, before IBM announced the character set. Previously
the customary use for | in logic was the "Scheffer stroke", which 
we now know as NAND. So "always" is ever since it became available. 
Was PL/I the first to adopt it?

Doug

[TUHS] Slashes

[John Cowan]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 986 bytes --]

Doug McIlroy scripsit:

> So "always" is ever since it became available. 

Yes, I meant that the meaning of | was never anything but "or" until it
came to be used as "pipe" (not only in shells but also in Perl and other
places), not that the representation of "or" has never been anything
but |.

> Was PL/I the first to adopt it?

I can't imagine anyone would do so until it was available.  The Algol
60 committee is a special case, with its distinction between publication
language, reference language, and implementation language.  The reference
language used ∨ (hence the proposed \/ convention); the existing
implementations use either "or" as a reserved word or else |.

-- 
John Cowan          http://www.ccil.org/~cowan        cowan at ccil.org
I come from under the hill, and under the hills and over the hills my paths
led. And through the air. I am he that walks unseen.  I am the clue-finder,
the web-cutter, the stinging fly. I was chosen for the lucky number.  --Bilbo

[TUHS] Slashes

[Tony Finch]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 1059 bytes --]

John Cowan <cowan at mercury.ccil.org> wrote:
>
> The Algol 60 committee is a special case, with its distinction between
> publication language, reference language, and implementation language.
> The reference language used ∨ (hence the proposed \/ convention); the
> existing implementations use either "or" as a reserved word or else |.

I am failing to remember where I have seen /\ and \/ used in the wild.

CPL's typeset descriptions have big mathematical conjunction and
disjunction operators. But I don't think I heard of composing them
out of slashes from the CPL literature.
http://comjnl.oxfordjournals.org/content/6/2/134.full.pdf+html

1960s BCPL manuals have a similar typographic convention to ALGOL 60.

The ALGOL 68 revised report defines all three of ∨| or for the
disjunction operator.

Tony.
-- 
f.anthony.n.finch  <dot at dotat.at>  http://dotat.at/  -  I xn--zr8h punycode
Fair Isle: Cyclonic, becoming westerly, except in far north, 5 or 6. Moderate
or rough. Rain or showers, fog patches. Moderate or good, occasionally very
poor.

[TUHS] Slashes

[John Cowan]

Tony Finch scripsit:

> I am failing to remember where I have seen /\ and \/ used in the wild.

I don't think anyone ever has used them; they were just a suggestion by
Bemer which induced him to lobby for \ in ASCII-63.

-- 
John Cowan          http://www.ccil.org/~cowan        cowan at ccil.org
The present impossibility of giving a scientific explanation is no proof
that there is no scientific explanation. The unexplained is not to be
identified with the unexplainable, and the strange and extraordinary
nature of a fact is not a justification for attributing it to powers
above nature.  --The Catholic Encyclopedia, s.v. "telepathy" (1913)

[TUHS] Slashes

[Christian Neukirchen]

John Cowan <cowan at mercury.ccil.org> writes:

> Tony Finch scripsit:
>
>> I am failing to remember where I have seen /\ and \/ used in the wild.
>
> I don't think anyone ever has used them; they were just a suggestion by
> Bemer which induced him to lobby for \ in ASCII-63.

It's used now in logic languages like Prolog and proof assistants like
Coq or TLA+.

-- 
Christian Neukirchen  <chneukirchen at gmail.com>  http://chneukirchen.org

[TUHS] Slashes (was: MS-DOS)

[Clem Cole]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 3402 bytes --]

On Fri, Jul 8, 2016 at 7:09 AM, Steffen Nurpmeso <steffen at sdaoden.eu> wrote:

> ...and that actually makes me wonder why the engineers that
> created what became POSIX preferred slash instead
>
​I can not speak for anyone else.   But at the time when I was a part of
the /usr/group UNIX standards** mtgs  I personally do not believe I had
ever heard of the term "​solidus." Such a term maybe had been used in my
first form Latin classes from the 1960s, but by the 1980s  I had long ago
forgotten any/all of my Latin.  I certainly did not try to remember it as a
computer professional.

In those days many of us, including me, did (and still do) refer to the
asterisk as "splat" and the exclamation point as "bang"  from the sound
made by them when they printed yellow oiled paper @ 10 cps from the console
TTY.  But slash was what we called the character that is now next to the
shift key on modern keyboards.   I do not remember ever using, much less
needed to refer to, the character "back slash" until the unfortunate crap
that the folks in Redmond forced on the industry.   Although interestingly
enough, the vertical bar or UNIX "pipe" symbol was used and discussed
freely in those days.   I find it interesting that Redmond-ism became the
unshifted character, not the vertical bar by the shear force of economics
of the PC.

Clem

** For those that do not know (my apologies to those that do) the 1985
/usr/group standards committee was the forerunner to IEEE P1003.  Which we
published as the first "official UNIX API standard agreed by the community"
(I still have a hardcopy).  But neither /usr/group nor USENIX had the
political authority to bring an official standard to FIPS, ANSI, ECMA, ISO
or like, while IEEE did.  So a few months before the last meeting, Jim
Issak petitioned IEEE for standards status, and the last meeting of the
/usr/group UNIX standards meeting was very short -- about 10 minutes.   We
voted to disband and then everyone in the room officially reformed a few
minutes later all signing in as IEEE P1003, later to be called POSIX.  For
further historical note, I was a "founding member" of both groups and the
editor of a number of early drafts (numbers 5-11 IIRC), as well as the
primary author of the Tape Format and Terminal I/O sections of P1003.1.
With Keith Bostic, I would later be part of the P1003.2 and pen the
original PAX compromise.  After that whole mess I was so disgusted with the
politics of the effort, I stopping going to the POSIX mtgs.

PPS While I did not work for them at the time, you can blame DEC for the
mess with the case/character sets in the POSIX & FIPS standards.   A number
of the compromises in the standard documents were forced by VMS, 7-bit
(case insensitivity) being the prime one.   While we did get in the
rational section of document that it was suggested/advised that systems
implementations and applications code be case insensitive and 8 bit clean
so that other character sets could be supported.  However the DEC folks
were firmly against anything more than 7-bit ASCII and supporting anything
in that character set. My memory is that the IBM folks were silent at the
time and just let the DEC guys carry the torch for 1960's 7-bit US English.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://minnie.tuhs.org/pipermail/tuhs/attachments/20160708/fdf012d6/attachment-0001.html>

[TUHS] Slashes (was: MS-DOS)

[Dave Horsfall]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 424 bytes --]

On Fri, 8 Jul 2016, Clem Cole wrote:

> In those days many of us, including me, did (and still do) refer to the 
> asterisk as "splat" and the exclamation point as "bang"  from the sound 
> made by them when they printed yellow oiled paper @ 10 cps from the 
> console TTY. 

I still remember when the pipe command was "^" (pointy hat).

-- 
Dave Horsfall DTM (VK2KFU)  "Those who don't understand security will suffer."

[TUHS] Slashes (was: MS-DOS)

[John Cowan]

Dave Horsfall scripsit:

> I still remember when the pipe command was "^" (pointy hat).

Thus forcing the rest of us to quote grep patterns like '^foo$' forever.

-- 
John Cowan          http://www.ccil.org/~cowan        cowan at ccil.org
An observable characteristic is not necessarily a functional requirement.
        --John Hudson

[TUHS] Slashes (was: MS-DOS)

[Milo Velimirovic]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 293 bytes --]


> On Jul 9, 2016, at 12:03 PM, John Cowan <cowan at mercury.ccil.org> wrote:
> 
> Dave Horsfall scripsit:
> 
>> I still remember when the pipe command was "^" (pointy hat).
> 
> Thus forcing the rest of us to quote grep patterns like '^foo$' forever.

It’s the $ that forces the quoting.

[TUHS] Slashes

[Christian Neukirchen]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 537 bytes --]

Milo Velimirovic <milov at cs.uwlax.edu> writes:

>> On Jul 9, 2016, at 12:03 PM, John Cowan <cowan at mercury.ccil.org> wrote:
>> 
>> Dave Horsfall scripsit:
>> 
>>> I still remember when the pipe command was "^" (pointy hat).
>> 
>> Thus forcing the rest of us to quote grep patterns like '^foo$' forever.
>
> It’s the $ that forces the quoting.

Not in POSIX-compatible sh (works in tcsh even):

$ echo see$
see$

(Neither does ^ need quoting there.)

-- 
Christian Neukirchen  <chneukirchen at gmail.com>  http://chneukirchen.org

[TUHS] Slashes (was: MS-DOS)

[Norman Wilson]

Steffen Nurpmeso:

  ...and that actually makes me wonder why the engineers that
  created what became POSIX preferred slash instead -- i hope it is
  not the proud of high skills in using (maybe light) sabers that
  some people of the engineer community seem to foster.  But it
  could be the sober truth.  Or, it could be a bug caused by
  inconsideration.  And that seems very likely now.

====

It had nothing to do with engineers.  `Slash' for / has been
conventional American usage for as long as I can remember,
dating back well before POSIX or UNIX or the movie that made
a meme of light sabers.

It's unclear exactly how far back it dates.  The earliest
OED citation for `slash' as `A thin sloping line, thus /'
is dated 1961; but the cite is from Webster's 3rd.

Given the amount of violence prevalent in American metaphor,
it is hardly noteworthy.

Make American Language Violent Again (and I HATE MOSQUITOS*).

Norman Wilson
Toronto ON

* If you don't know what this refers to, you probably don't
want to know.

[TUHS] Slashes

[Adam Sampson]

norman at oclsc.org (Norman Wilson) writes:

> It's unclear exactly how far back it dates.  The earliest OED citation
> for `slash' as `A thin sloping line, thus /' is dated 1961; but the
> cite is from Webster's 3rd.

A bit of searching finds earlier American examples in the context of
livestock brands. For example, from "Hot Irons: Heraldry of the Range",
1940:

  A crude sign at a dirt turnoff will have been "painted" with a hot
  iron, reading V-/ 8.

  You may or may not know that the V Bar Slash ranch house is eight
  miles down that trail [...]

Or in State v. Craig, New Mexico, 1922:

  The calves were then placed in a corral at the Webber ranch, and
  several days later were branded by appellant with A slash brand and
  then turned into the open pasture.

-- 
Adam Sampson <ats at offog.org>                         <http://offog.org/>