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Safari 10.1 `nomodule` support
/**
* Safari 10.1 supports modules, but does not support the `nomodule` attribute - it will
* load <script nomodule> anyway. This snippet solve this problem, but only for script
* tags that load external code, e.g.: <script nomodule src="nomodule.js"></script>
*
* Again: this will **not** prevent inline script, e.g.:
* <script nomodule>alert('no modules');</script>.
*
* This workaround is possible because Safari supports the non-standard 'beforeload' event.
* This allows us to trap the module and nomodule load.
*
* Note also that `nomodule` is supported in later versions of Safari - it's just 10.1 that
* omits this attribute.
*/
(function() {
var check = document.createElement('script');
if (!('noModule' in check) && 'onbeforeload' in check) {
var support = false;
document.addEventListener('beforeload', function(e) {
if (e.target === check) {
support = true;
} else if (!e.target.hasAttribute('nomodule') || !support) {
return;
}
e.preventDefault();
}, true);
check.type = 'module';
check.src = '.';
document.head.appendChild(check);
check.remove();
}
}());
/**
* Minified-ish version of the above.
*/
(function() {
var d = document;
var c = d.createElement('script');
if (!('noModule' in c) && 'onbeforeload' in c) {
var s = false;
d.addEventListener('beforeload', function(e) {
if (e.target === c) {
s = true;
} else if (!e.target.hasAttribute('nomodule') || !s) {
return;
}
e.preventDefault();
}, true);
c.type = 'module';
c.src = '.';
d.head.appendChild(c);
c.remove();
}
}());

This is pretty smart!

anilanar commented Jun 25, 2017 edited

Safari 10.1 still downloads the nomodule file, but it doesn't execute.

My fork: https://gist.github.com/anilanar/5be4897eb2ef261ff53a778e3fe5f2d3
Not as easy to use as the original one as scripts are injected at runtime.

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