Logging¶
Sometimes the information that is available statically, by just reading the HTML, may not be enough and you may need to peek into the runtime value of some important variable.
With a well-designed API, such situations should be rare. But, unfortunately, the real world is messy and they cannot be fully avoided.
This is where the dedicated log attribute comes in.
It will do nothing at all most of the time and is generally harmless to add, even to every single element. However, it is still a debugging flag and, from a purely aesthetic point of view, should not be left enabled in production.
All that it will ever do is log to the JavaScript console some information that the element deems important at a particular moment in time.
Info
Currently, this attribute only logs event objects in the presence of an
event:<event name> attribute, right before performing the matching for
it. But, the log attribute itself is meant to be general purpose and its
functionality may be extended in the future.
Example¶
When this input receives a keydown event, KEML logs the browser event object
before checking if the key is Enter.
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What if you don't know what fields the event object has or what values they can take?
In that case, simply leave the event:keydown attribute empty, trigger the
event, and observe the event object printed to the console — on:keydown must
still have a value, otherwise KEML will skip matching it.
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