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When should I create a destructor?
...here could have been a thread abort halfway through writing the double and now the finalizer has to deal with a half-initialized half-zero double.
– Eric Lippert
Mar 31 '11 at 14:11
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Conversion from Long to Double in Java
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I did. Parsing a string to do this (now edited out of the answer) will degrade performance by many orders of magnitude. Boxing is less expensive but still worth avoiding, especially in cases like this (using new) where it can't be elided away.
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How do I get the object if it exists, or None if it does not exist?
...u can do it this way:
go = Content.objects.filter(name="baby").first()
Now go variable could be either the object you want or None
Ref: https://docs.djangoproject.com/en/1.8/ref/models/querysets/#django.db.models.query.QuerySet.first
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PHP Fatal error: Using $this when not in object context
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@Sarfraz it's better now. Sorry for pestering you, but as this became the accepted answer, I felt it necessary to point these things out :) Thanks for your patience.
– Gordon
Feb 28 '10 at 13:00
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Why does AngularJS include an empty option in select?
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This may work for now, but the angular documentation specifically recommends against using ng-init for anything besides ng-repeat - see docs.angularjs.org/api/ng/directive/ngInit
– Ed Norris
Aug 8 '14 at ...
Rails: update_attribute vs update_attributes
...nd(name.to_s + '=', value)
2616: save(false)
2617: end
and now refer update_attributes and look at its code you get
# File vendor/rails/activerecord/lib/active_record/base.rb, line 2621
2621: def update_attributes(attributes)
2622: self.attributes = attributes
26...
Can an Android NFC phone act as an NFC tag?
... NFC phone will act as an NFC reader which will read data from an NFC tag. Now my question is, can we switch this around? Can we make an Android NFC phone behave as the tag which an NFC reader will get data from?
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Ignoring time zones altogether in Rails and PostgreSQL
...m the Postgres epoch, 2000-01-01 00:00:00 UTC.
Postgres also has built-in knowledge of the commonly used UNIX time counting seconds from the UNIX epoch, 1970-01-01 00:00:00 UTC, and uses that in functions to_timestamp(double precision) or EXTRACT(EPOCH FROM timestamptz).
The source code:
* Timestam...
Develop Android app using C#
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@cmroanirgo Xamarin now supports a subscription based model with a free option - you no longer need to buy Mono for Android.
– James
Oct 18 '13 at 14:08
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How to declare string constants in JavaScript? [duplicate]
...t serves a similar purpose
FOO : "foofoo",
BAR : "barbar",
}
You can now print out 'foofoo' with
jsEnum.FOO
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