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Ruby on Rails Callback, what is difference between :before_save and :before_create?
Could you explain in detail what the :before_save and :before_create Ruby on Rails callbacks are, and what they have to do with Rails validations? Does validation occur after :before_save or :before_create ?
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What is the use of the JavaScript 'bind' method?
...clicked
You can also add extra parameters after the 1st (this) parameter and bind will pass in those values to the original function. Any additional parameters you later pass to the bound function will be passed in after the bound parameters:
// Example showing binding some parameters
var sum = f...
Vertically align text next to an image?
Why won't vertical-align: middle work? And yet, vertical-align: top does work.
23 Answers
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Dynamically creating keys in a JavaScript associative array
...rk well, are overcomplicated:
They use new Array(), which is an overkill (and an overhead) for a simple associative array (AKA dictionary).
The better ones use new Object(). It works fine, but why all this extra typing?
This question is tagged "beginner", so let's make it simple.
The über-simple ...
How do I put an already-running process under nohup?
I have a process that is already running for a long time and don't want to end it.
11 Answers
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Rollback to last git commit
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Caveat Emptor - Destructive commands ahead.
Mitigation - git reflog can save you if you need it.
1) UNDO local file changes and KEEP your last commit
git reset --hard
2) UNDO local file changes and REMOVE your last commit
git reset --hard HEAD^
3)...
Which mime type should I use for mp3
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Chrome 26 knows better and uses audio/mp3... Go figure.
– Nux
Apr 5 '13 at 11:31
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Using Rails serialize to save hash to database
...wrong, :text
end
Then Rails will properly convert it into YAML for you (and perform proper serialization). Strings fields are limited in size and will only hold especially-small values.
share
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Permission denied on accessing host directory in Docker
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See this Project Atomic blog post about Volumes and SELinux for the full story.
Specifically:
This got easier recently since Docker finally merged a patch which
will be showing up in docker-1.7 (We have been carrying the patch in
docker-1.6 on RHEL, CentOS, and Fe...
how to hide a vertical scroll bar when not needed
I have a textarea which is contained in a div as I have jquery hint and wanted to use opacity without changing the border.
There is a visible vertical scroll bar how I only want this displayed when I am typing in the text field and it goes beyond the container. I have tried overflow: auto; but does ...