Re: [Tools-discuss] UTF-8 box characters with wavy lines in XML2RFC v3 draft

Adam Roach <> Wed, 06 November 2019 04:46 UTC

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To: Tom Pusateri <>
Cc: Tom Pusateri <>, tools-discuss <>, "Heather Flanagan (RFC Series Editor)" <>
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From: Adam Roach <>
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Date: Tue, 5 Nov 2019 22:46:40 -0600
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Subject: Re: [Tools-discuss] UTF-8 box characters with wavy lines in XML2RFC v3 draft
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On 11/5/19 8:39 PM, Tom Pusateri wrote:
> We were told on this list that box characters were allowed in artwork.

That's not on my radar. I'll let Heather (copied) chime in with her 

In any case, the *general* problem you're running into is that many 
monospaced fonts don't include much more than the basic accented Latin 
character set, and this results in substituting glyphs from other fonts 
(rather than rendering tofu or the questionmark "replacement character") 
that are of a different width than the fixed one used by the font in 

This is why, had the question come up generally, I would have pushed 
back on the notion of using box characters in diagrams [1]: even if it 
works okay on your system, it's likely to fail on someone's.

The *specific* problem you're running into is that Roboto Mono (or 
whatever your system uses as the default monospace font if you don't 
have Roboto Mono installed) doesn't contain "▶", and so it's getting 
pulled in from some other font, where it's wider.


[1] That is, absent some compelling data showing that they are generally 
available in all -- or at least the vast majority of -- popular 
fixed-width fonts. I think the current episode shows where such an 
assertion would be implausible.