Lit-element: if the value is undefined, then attribute being created

[Leon-Alexey]

do as it was, if the value is undefined, the attribute should not be created

version 0.6:
<a href="${item.link}" ></a> --> <a href="undefined"></a>

version 0.5.2:
<a href="${item.link}" ></a> --> <a></a>

[web-padawan]

@Leon-Alexey please read the changelog and docs carefully before starting to complain.
The binding notation has been changed in 0.5.2 so you should now bind to a property:

<a .href="${item.link}"></a>

[Leon-Alexey]

<a .href="${item.link}"></a>

It's not working

[Leon-Alexey]

if (item.link !== undefined) { return html'<a href="${item.link}"></a>' } else { retun html'<a></a>' }

if need add 10 attributes then to make 10 'if'

[web-padawan]

@Leon-Alexey ok, the href is still attribute, so the proper solution would be to use directive:

import { ifDefined } from 'lit-html/directives/if-defined.js';

and then use it like this:

<a href="${ifDefined(item.link)}"></a>

See working demo here: https://glitch.com/edit/#!/linen-bonsai?path=index.html:17:4

[Leon-Alexey]

works, Thanks!