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Python unittest - opposite of assertRaises?
...r test must exit with a failure condition, not an error one. On the other hand, if in running the same code you would raise a KeyError, that would be an error, not a failure. In python - differently than some other languages - Exceptions are routinely used for control flow, this is why we have the e...
Should an Enum start with a 0 or a 1?
...ag enum values of zero unless the value represents "all flags are cleared" and is named appropriately, as prescribed by the next guideline.
✔️ DO name the zero value of flag enums None. For a flag enum, the value must always mean "all flags are cleared."
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How to append rows to an R data frame
...rs of the type you want for each column, insert values into those vectors, and then, at the end, create your data.frame.
Continuing with Julian's f3 (a preallocated data.frame) as the fastest option so far, defined as:
# pre-allocate space
f3 <- function(n){
df <- data.frame(x = numeric(n)...
How can I measure the speed of code written in PHP? [closed]
... two solutions :
The quite "naïve" one is using microtime(true) tobefore and after a portion of code, to get how much time has passed during its execution ; other answers said that and gave examples already, so I won"t say much more.
This is a nice solution if you want to benchmark a couple of in...
Understanding Fragment's setRetainInstance(boolean)
...you leave the Activity by pressing the back button (thus, calling finish() and effectively destroying the Activity), all of the Activitys attached Fragments will also be destroyed.
Why doesn't it work with fragments on the back stack?
There are probably multiple reasons why it's not supported,...
Best practice to mark deprecated code in Ruby?
...a method as deprecated, so the people using it can easily check their code and catch up. In Java you set @Deprecated and everybody knows what this means.
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Search and replace in Vim across all the project files
I'm looking for the best way to do search-and-replace (with confirmation) across all project files in Vim. By "project files" I mean files in the current directory, some of which do not have to be open.
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setting an environment variable in virtualenv
...017 the README of autoenv states that direnv is probably the better option and implies autoenv is no longer maintained.
Old answer
I wrote autoenv to do exactly this:
https://github.com/kennethreitz/autoenv
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How does push notification technology work on Android?
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From what I've heard during an Android developers conference in Israel:
There is simply a TCP socket waiting in accept mode on a cloud Google server. The TCP connection had been initiated by the Google Play application. That's why Google Play must be inst...
Stretch and scale a CSS image in the background - with CSS only
I want that my background image stretch and scale depending on the browser viewport size.
22 Answers
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