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mathiasbynens/LICENSE.txt

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Created June 11, 2011 08:56
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Quick and dirty way to check if a given string can be used as an unquoted attribute value in HTML. (50 bytes)
Raw
README.txt
So, after cross-referencing these three different sections of the HTML
spec, we can finally conclude that a valid unquoted attribute value in
HTML is any string of text that is not the empty string and that doesn’t
contain spaces, tabs, line feeds, form feeds, carriage returns, ", ', `,
=, <, or >.
→ See http://mathiasbynens.be/notes/unquoted-attribute-values
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annotated.js
function(value) {
return /^[^ \t\n\f\r"'`=<>]+$/.test(value);
}
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index.js
function(v){return/^[^ \t\n\f\r"'`=<>]+$/.test(v)}
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LICENSE.txt
DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
Version 2, December 2004
Copyright (C) 2011 Mathias Bynens <http://mathiasbynens.be/>
Everyone is permitted to copy and distribute verbatim or modified
copies of this license document, and changing it is allowed as long
as the name is changed.
DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
0. You just DO WHAT THE FUCK YOU WANT TO.
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package.json
{
"name": "unquotedHTMLAttributeValueValidator",
"description": "Check if a given string can be used as an unquoted attribute value in HTML.",
"keywords": [
"html",
"attribute",
"attribute-values"
]
}
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test.html
<!DOCTYPE html>
<!-- Demo: http://mothereffingunquotedattributes.com/ -->
<title>Unquoted attribute value validator</title>
<input value="foo'bar" required autofocus> is <em>not</em> a valid unquoted attribute value.
<script>
var isUnquotable = function(v){return/^[^ \t\n\f\r"'`=<>]+$/.test(v)},
el = document.getElementsByTagName('em')[0];
document.getElementsByTagName('input')[0].oninput = function() {
el.style.display = isUnquotable(this.value) ? 'none' : 'inline';
};
</script>
@tsaniel
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tsaniel commented Nov 12, 2011

You could just rewrite the code and test here and see what went wrong http://jsfiddle.net/mathias/cYKrV/.

@maettig
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maettig commented Nov 12, 2011

You are testing if your regular expression does not match certain whitespace characters. But according to the Whitespace deviations chart all these characters are whitespace characters, at least in modern browsers. If you ask me, I don't care about the higher whitespace characters. If they are matched with \s it's fine. If they are not matched (because the JavaScript is run in an older browser) I don't care because almost nobody uses these characters.

@tsaniel
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tsaniel commented Nov 12, 2011

I agree that those characters are unusual, however, replacing with the \s doesn't save many bytes, I think it's not worth it.

@maettig
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maettig commented Nov 12, 2011

It's true. If you want to stick with the specification where certain characters do not count as whitespace characters, you can not use \s.

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