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How do I get the first element from an IEnumerable in .net?
...often want to grab the first element of an IEnumerable<T> in .net, and I haven't found a nice way to do it. The best I've come up with is:
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Override Python's 'in' operator?
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Zoran, I agree, and I even upvoted this answer and not the other. I'm just pointing out that a truly good answer should always link to docs, if available.
– Peter Hansen
Aug 31 '12 at 21:55
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What does denote in C# [duplicate]
I'm new to C# and directly diving into modifying some code for a project I received. However, I keep seeing code like this :
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What is the best way to uninstall gems from a rails3 project?
...he Gemfile. I thought (mistakenly) that if I deleted a gem from my Gemfile and ran 'bundle install' that the deleted gems would be uninstalled. I've looked at the bundler help file and, so far as I can tell, it does not have a way to uninstall gems.
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How does bash tab completion work?
I have been spending a lot of time in the shell lately and I'm wondering how the tab autocomplete works. What's the mechanism behind it? How does the bash know the contents of every directory?
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How can I find out the current route in Rails?
...ent_uri as "/my/test/path"
To find out the route i.e. controller, action and params:
path = ActionController::Routing::Routes.recognize_path "/your/path/here/"
# ...or newer Rails versions:
#
path = Rails.application.routes.recognize_path('/your/path/here')
controller = path[:controller]
action...
Meaning of epsilon argument of assertEquals for double values
... The documentation says, "delta - the maximum delta between expected and actual for which both numbers are still considered equal." So I think that should be a <= not <.
– Andrew Cheong
Apr 16 '18 at 17:00
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Use Font Awesome Icon in Placeholder
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You can't add an icon and text because you can't apply a different font to part of a placeholder, however, if you are satisfied with just an icon then it can work. The FontAwesome icons are just characters with a custom font (you can look at the F...
Xcode iOS project only shows “My Mac 64-bit” but not simulator or device
... it out. I had to edit the scheme (Product->Scheme->Edit Scheme...), and for some reason no executable was selected. I chose my app, saved and now I have my simulator and device options back.
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What is causing ERROR: there is no unique constraint matching given keys for referenced table?
...R: there is no unique constraint matching given keys for referenced table, and having stared at it for while now I can't figure out why this error arises in this situation.
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