Re: [netmod] artwork folding: dual support modes?

"Rob Wilton (rwilton)" <> Wed, 27 February 2019 10:09 UTC

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From: "Rob Wilton (rwilton)" <>
To: "" <>, 'Joel Jaeggli' <>
CC: "" <>
Thread-Topic: [netmod] artwork folding: dual support modes?
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Date: Wed, 27 Feb 2019 10:09:51 +0000
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Subject: Re: [netmod] artwork folding: dual support modes?
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Hi Adrian,

I mostly agree with your last sentence.

I think that if you always preserve whitespace then a single slash is fine.  I.e. the single slash just breaks the line, and I think that this matches how editors, programming languages, etc normally behave.

What I’m not keen on is using a single slash, and then automatically stripping leading whitespace on the line following a slash.

If we want to have control of layout and be able to strip extra whitespace then my argument is that it is better to be explicit, and using two slashes is one way of achieving this.


From: netmod <> On Behalf Of Adrian Farrel
Sent: 27 February 2019 09:41
To: 'Joel Jaeggli' <>
Subject: Re: [netmod] artwork folding: dual support modes?

Complete agreement, Joel.

What follows may look better in proportional fonts.

With a single slash we can wrap as follows

1234567        9012345

Goes to…

1234567    \

…and unwrapping is easy.

However, if I want to manually wrap the line with indentation

The quick brown fox jumps over the lazy dog

..going to…

The quick brown fox\
      jumps over the lazy dog

…I am going to unfold as…

The quick brown fox      jumps over the lazy dog

Conversely, if I resolve this second case by stripping leading spaces I get…

The quick brown foxjumps over the lazy dog

So I have to fold as…

The quick brown fox \
      jumps over the lazy dog

But this causes the first case to unfold as

1234567    9012345

…i.e., with missing spaces.

This is what caused the use of the second slash so…

1234567    \
\    9012345


The quick brown fox\
     \ jumps over the lazy dog

So, my point is, if and only if we do not care about these “spaces on the fold” cases, we can operate with a single slash.


From: Joel Jaeggli <<>>
Sent: 27 February 2019 06:31
To: Adrian Farrel <<>>
Cc: Kent Watsen <<>>;<>
Subject: Re: [netmod] artwork folding: dual support modes?

On Feb 26, 2019, at 14:26, Adrian Farrel <<>> wrote:


I’ve been having this discussion with Kent off-line, but thought it should come to the list.

I don’t think it is a good idea to have two approaches. While it would be relatively easy to code for both approaches, it seems to add a degree of confusion if both have to be handled by the same code (consider deciding whether leading space characters are to be retained or not, something that can only be decided when the first non-space character is found), or by having different code for the two different cases.

It doesn’t seem to me that both cases are needed. We can pick one or the other.

A single slash has been used to wrap long lines in editors and shells for decades at this point.

and yeah whatever it is one method seems better than two.

And *if* we want to allow manual folding so that indents can be made to make the document more human-readable then we have to use a leading ‘\’ on continuation lines to show which spaces should be stripped and which retained.


From: netmod <<>> On Behalf Of Kent Watsen
Sent: 25 February 2019 22:22
Subject: [netmod] artwork folding: dual support modes?

I had a chat with the tools team recently and, in the course of things, it was implied
that the double backslash approach we have now was both surprising and non-intuitive.

This got me thinking that we may have thrown the proverbial baby out with the bathwater.
That is, currently we have a header that reads:

  NOTE: '\\' line wrapping per BCP XX (RFC XXXX)

So why not *also* support a header that reads (note the singe slash):

  NOTE: '\' line wrapping per BCP XX (RFC XXXX)

Whereby this second form only supports the folded line continuing on column 1 (no indents).


Kent // contributor

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