Is 78 characters still a good option? Was: [Haskell-cafe] breaking too long lines

Richard O'Keefe ok at
Wed Apr 22 19:37:45 EDT 2009

On 22 Apr 2009, at 8:09 pm, Jason Dusek wrote:

>  Really, the whole thing makes me wish we had blasphemy laws.
>    If any person, in speaking or in writing, shall indicate
>    a preference for column widths other than 80 or indent
>    characters other than spaces (`0x20`) they shall be
>    compelled to present some science or be subject to
>    imprisonment.

I did find a paper that claimed that 95-character lines were
significantly faster to read than three shorter lengths.  On
closer study, it turned out that they were using the "paging"
model rather than the "scrolling" model:  once you came to
the end of a (short) page of text, you had to hit the Next
button to see the next page.  What they had in fact proved
was that hitting the Next Page button takes time...

Now that I have access to a recent Mac laptop, I've found that
in reading plain text, I like to make the lines narrower and
to approximate continuous scrolling: read one paragraph, stroke
the pad to move the next one up, keep on doing it.

There are several important differences between program text
and ordinary running natural language text.  In particular,
program text is two-dimensional in a way that ordinary text
is not.

By the way, in the era of punched cards, while the *cards*
were 80 columns, one's *text area* was not.  Typically the
last 8 columns were used for a sequence number, so that if
you dropped your cards -- yes, this happened -- you could
sort them back into order, and to provide editing facilities.
So people were really programming with 72-column lines.
That seemed to work pretty well, and printers seemed to have
no trouble reproducing it in books.

I do know a psychologist who has done reading studies; I
must see if I can talk him into looking into this.

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