element "u" not allowed anywhere

[JLius]

Hi all

So I'm at the final stage of my epub-novel and ran a validation. I get this error message about a hundred times:

element "u" not allowed anywhere; expected the element end-tag, text or element "a", "abbr", "acronym", "applet", "b", "bdo", "big", "br", "cite", "code", "del", "dfn", "em", "i", "iframe", "img", "ins", "kbd", "map", "noscript", "ns:svg", "object", "q", "samp", "script", "small", "span", "strong", "sub", "sup", "tt" or "var" (with xmlns:ns="http://www.w3.org/2000/svg")

From what I've read, the <u> shouldn't be a problem as long as it is within a <p>.
This is what it all looks like in my html:

<p><u>some text</u></p>

So, what exactly is the problem here? I used the calibre editor, and it has this toolbar with the "u", "b", "I" etc, so I just (ignorantly?)used it...

What should I do to fix this, and is there an easy way to fix all 100 instances at once? I've heared of regex, but I don't master it yet (not by a long shot). Any help would be grately appreciated, as always.

Yours

Johan

[DaleDe]

You can replace <u> with <span class="u"> even without regexpession and then do the same with </u> to </span> and then write a .u entry in CSS to perform the underlining.

Dale

[mzmm]

you could use the following regex to replace all instances, although i would recommend against blindly doing a global replace, better to go through one-by-one (more or less automated in Sigil with 'Search in all XHTML files' and then clicking 'Replace/Find Next').

find:
<u>(.*?)</u>

replace:

<span class="underline">\1</span>

then in your stylesheet you'd

.underline{
    text-decoration:underline;
}

if you are using Sigil, remember to make sure the regex search is selected in the find/replace bar

[skreutzer]

As the error message clearly points out, you're not allowed to use <u> anywhere, since <u> is a deprecated element in HTML4 Strict and XHTML Strict. Does Calibre place an <u> in the EPUBs XHTML when clicking on an “underline” button?

[mrmikel]

It is one of those things which will work in actual readers, but which validators don't like. Not a problem if for personal use, but publishers will use one or another of them.

Underlining is very old school, as there are other ways to emphasize by bolding, italicizing, increasing the font size, etc. About the only use I could see for it these days would be to try to create a form to be filled out. But there are even better ways to do that. The main use would be to copy an original that used them.

One of the issues is that underlining can be confused with links, so that hastened its way out the door.

[skreutzer]

Rendering software should be quite tolerant regarding validity, processing tools should not be required to be overly tolerant to all kinds of non-standard data junk, and creation tools should absolutely follow a zero tolerance policy. The fact that underlining is bad typography is a separate issue besides technical correctness. Syntactical and semantical correctness are the bare minimum for 21st century web and e-book technology.

[JLius]

Originally Posted by skreutzer

As the error message clearly points out, you're not allowed to use <u> anywhere, since <u> is a deprecated element in HTML4 Strict and XHTML Strict. Does Calibre place an <u> in the EPUBs XHTML when clicking on an “underline” button?

Yes, the calibre editor has an underline button on the toolbar that places a <u> in your html file. Doesn't Kovid Goyal know that the <u> is a deprecated element? That would be weird, no? I really thought Goyal was omniscient

Thanks for the tips, I'll try and implement them this evening (European time ).

[Toxaris]

To be fair, <b> and <i> are also deprecated but no warnings will be given for those. Honestly I do not see them go away very soon either...

[JLius]

Should I post on the editor forum that the editor toolbar has deprecated elements? Or do you think Goyal has a good reason to be still using them?

[odedta]

Originally Posted by JLius

Should I post on the editor forum that the editor toolbar has deprecated elements? Or do you think Goyal has a good reason to be still using them?

Differences Between HTML 4.01 and HTML5
The <u> element was deprecated in HTML 4.01. (the <u> element was used to define underlined text).

The <u> element is redefined in HTML5, to represent text that should be stylistically different from normal text, such as misspelled words or proper nouns in Chinese.

Reference: http://www.w3schools.com/Tags/tag_u.asp

[JLius]

Sure, but how does that answer my question? The toolbar in the editor uses the <u> element to underline text, not to write in Chinese.

[odedta]

It's an element you can use, you can always define it's style in your stylesheet.

In a couple of hours when I'm back home I'll check this thoroughly.

[skreutzer]

No, you can't (in EPUB at least):

http://www.idpf.org/epub/20/spec/OPS...htm#Section2.2

Since it was already deprecated, I guess they just threw it out in order to define a more futuristic use of HTML elements.

[JLius]

I posted it on the editor forum, maybe Goyal has an explanation.

https://www.mobileread.com/forums/sho...09#post2812109

[JLius]

And he did. I should just ignore the errors, epub validation is a waste of time.

Cheers y'all!