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mongodb: insert if not exists
... specify what data you want to write:
data = {"$set":{"key2":"value2"}}
Now your selected document will update the value of "key2" only and leave everything else untouched.
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Looping in a spiral
...wered Oct 12 '09 at 15:29
Tom J NowellTom J Nowell
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Making the Android emulator run faster
...
UPDATE: Now that an Intel x86 image is available, the best answer is by zest above.
As CommonsWare has correctly pointed out, the emulator is slow because it emulates an ARM CPU, which requires translation to Intel opcodes. This vir...
How do I create and read a value from cookie?
...name, value, days = 7, path = '/') => {
const expires = new Date(Date.now() + days * 864e5).toUTCString()
document.cookie = name + '=' + encodeURIComponent(value) + '; expires=' + expires + '; path=' + path
}
const getCookie = (name) => {
return document.cookie.split('; ').reduce((r, v)...
Proper way to wait for one function to finish before continuing?
...ne!');
});
}
As per @Janaka Pushpakumara's suggestion, you can now use arrow functions to achieve the same thing. For example:
firstFunction(() => console.log('huzzah, I\'m done!'))
Update: I answered this quite some time ago, and really want to update it. While callbacks are abso...
When are you truly forced to use UUID as part of the design?
I don't really see the point of UUID . I know the probability of a collision is effectively nil , but effectively nil is not even close to impossible.
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Who is calling the Java Thread interrupt() method if I'm not?
...ly should not call System.exit(). (Your application does not necessarily know why it was interrupted, and it certainly does not know if there are other threads that need to be interrupted by the framework.)
On the other hand, if your code is not designed to run under the control of some framewor...
What's the difference between URI.escape and CGI.escape?
...es how data should be encoded/decode between web server and application.
Now, let's say that you need to escape a URI in your app. It is a more specific use case.
For that, the Ruby community used URI.escape for years. The problem with URI.escape was that it could not handle the RFC-3896 spec.
UR...
WPF Blurry fonts issue- Solutions
...e on the WPF Text Blog explaining the changes. Most prominently, there are now (at least) three different kinds of text rendering:
<grumble>That should be enough rope for every designer.</grumble>
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How to make an Android Spinner with initial text “Select One”?
...e from above into your project, e.g. into package com.example.customviews. Now in your layout xml, instead of <Spinner ...> use <com.example.customviews.NoDefaultSpinner ...> The rest of the code can stay the same. Don't forget to add the android:prompt attribute to the <com.example.c...