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What exactly is nullptr?
...constant can be converted to std::nullptr_t. The opposite direction is not allowed. This allows overloading a function for both pointers and integers, and passing nullptr to select the pointer version. Passing NULL or 0 would confusingly select the int version.
A cast of nullptr_t to an integral ty...
MySQL SELECT WHERE datetime matches day (and not necessarily time)
I have a table which contains a datetime column. I wish to return all records of a given day regardless of the time. Or in other words, if my table only contained the following 4 records, then only the 2nd and 3rd would be returned if I limit to 2012-12-25.
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How to convert a std::string to const char* or char*?
... Notice that the above is not exception safe. If anything between the new call and the delete call throws, you will leak memory, as nothing will call delete for you automatically. There are two immediate ways to solve this.
boost::scoped_array
boost::scoped_array will delete the memory for you upo...
Testing if jQueryUI has loaded
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my problem is that I load jQuery and jQuery.ui dynamically. It sometimes loads in time, sometimes not. If ui is not loaded, how can I wait for it (or force it to be loaded) before calling any method?
– Gabriel Diaconescu
Sep 14 '11 at 10:10...
When to use EntityManager.find() vs EntityManager.getReference() with JPA
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I usually use getReference method when i do not need to access database state (I mean getter method). Just to change state (I mean setter method). As you should know, getReference returns a proxy object which uses a powerful featu...
Why call git branch --unset-upstream to fixup?
.... Once local branch L is set to track remote-tracking branch R, Git will call R its "upstream" and tell you whether you're "ahead" and/or "behind" the upstream (in terms of commits). It's normal (even recommend-able) for the local branch and remote-tracking branches to use the same name (except fo...
Scratch还是App Inventor？低代码编程工具2026终极横评：谁才是真正的入门...
...用Designer拖组件，逻辑层用Blocks拼积木，数据层用TinyDB或Web API对接后端。这个分层架构，和你在阿里、腾讯看到的真实项目没有本质区别。
场景3：物联网与硬件探索
到了2026年，IoT教育已经不再是大学实验室的专利。Scratch...
GDB missing in OS X v10.9 (Mavericks)
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I installed via brew, and keep getting "_____: not in executable format: File format not recognized" when I try to load an executable. Can anyone comment on how they got a successful install?
– Parker
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Why does sudo change the PATH?
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Yeah, but it's totally counterintuitive. It probably fools the good guys more than the bad guys.
– Brian Armstrong
Jun 20 '09 at 2:24
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Django in / not in query
...e(); Tbl2.objects.filter(id__in=IDs') This did not work because IDs is actually a QuerySet object. When I deleted the rows it originated from, it no longer worked with other queries. The solution is Tbl2.objects.filter(id__in=list(IDs)) -- turn it into a list
– Dakusan
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