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Why does Clojure have “keywords” in addition to “symbols”?
I have a passing knowledge of other Lisps (particularly Scheme) from way back. Recently I've been reading about Clojure . I see that it has both "symbols" and "keywords". Symbols I'm familiar with, but not with keywords.
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How do I remove lines between ListViews on Android?
I'm using two ListView s like this:
12 Answers
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Is it better to return null or empty collection?
That's kind of a general question (but I'm using C#), what's the best way (best practice), do you return null or empty collection for a method that has a collection as a return type ?
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Correct way to detach from a container without stopping it
In Docker 1.1.2 (latest), what's the correct way to detach from a container without stopping it?
10 Answers
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How to sum a variable by group
I have a data frame with two columns. First column contains categories such as "First", "Second", "Third", and the second column has numbers that represent the number of times I saw the specific groups from "Category".
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Android file chooser [closed]
...I hence I need a file chooser but I don't want to write this by myself. I find OI file manager and I think it suits me.
But how can I force user to install OI file manager?
If I cannot , is there a better way to include a file manager in my app?
Thx
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Rollback a Git merge
I use git merge --no-ff develop to merge any upstream changes into dashboard
5 Answers
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Test iOS app on device without apple developer program or jailbreak
How can I test an iOS application on my iPod Touch without registering for the Apple Developer Program or jailbreaking my iPod?
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How to perform OR condition in django queryset?
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from django.db.models import Q
User.objects.filter(Q(income__gte=5000) | Q(income__isnull=True))
via Documentation
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How to avoid mysql 'Deadlock found when trying to get lock; try restarting transaction'
I have a innoDB table which records online users. It gets updated on every page refresh by a user to keep track of which pages they are on and their last access date to the site. I then have a cron that runs every 15 minutes to DELETE old records.
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