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Assignment in an if statement

... = value as T; if (t != null) { action(t); } } Then call it with: animal.AsIf<Dog>(dog => { // Use dog in here }); Alternatively, you could combine the two: public static void AsIf<T>(this object value, Action<T> action) where T : class { // EVI...
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How to 'bulk update' with Django?

...ings like incrementing rows: from django.db.models import F Entry.objects.all().update(n_pingbacks=F('n_pingbacks') + 1) See the documentation. However, note that: This won't use ModelClass.save method (so if you have some logic inside it won't be triggered). No django signals will be emitte...
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Call a python function from jinja2

I am using jinja2, and I want to call a python function as a helper, using a similar syntax as if I were calling a macro. jinja2 seems intent on preventing me from making a function call, and insists I repeat myself by copying the function into a template as a macro. ...
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std::vector performance regression when enabling C++11

I have found an interesting performance regression in a small C++ snippet, when I enable C++11: 1 Answer ...
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What is the use of “assert” in Python?

...t True # nothing happens >>> assert False Traceback (most recent call last): File "<stdin>", line 1, in <module> AssertionError Assertions can include an optional message, and you can disable them when running the interpreter. To print a message if the assertion fails: ass...
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MFC 的SetWindowPos 用法 - C/C++ - 清泛网 - 专注C/C++及内核技术

...window, the window loses its topmost status and is placed at the bottom of all other windows. HWND_NOTOPMOST= -2 在所有非"普通层"之上的"普通层" Places the window above all non-topmost windows (that is, behind all topmost windows). This flag has no effect if the window is already a n...
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How can I handle R CMD check “no visible binding for global variable” notes when my ggplot2 syntax i

... Just another warning. aes_string does not allow you to use functions to manipulate the x and y values. Say that you would like to log transform y in which case aes_string(x = 'x.values', y='log(y.values)') of course doesn't work. I use these kind of transformations a...
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How can I do division with variables in a Linux shell?

... It has to be noted somewhere on this page that most (if not all) GNU/Linux shells only perform integer operations. – Skippy le Grand Gourou Sep 19 '14 at 12:47 ...
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Error - trustAnchors parameter must be non-empty

...and what truststore is being used you can add the property javax.net.debug=all and then filter the logs about truststore. You can also play with the property javax.net.ssl.trustStore to specify a specific truststore. For example : java -Djavax.net.debug=all -Djavax.net.ssl.trustStore=/Another/...
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How to change language settings in R

... of the abbreviations can be found here. Sys.getenv() gives you a list of all the environment variables that are set. share | improve this answer | follow | ...