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When vectors are allocated, do they use memory on the heap or the stack?
... the heap and header info is on the stack, when the header info is removed from memory, like function return, what will happen to the elements memories? Are them reclaimed with the header info or not? If they are not, will this cause memory leak?
– flyrain
Sep ...
How does “make” app know default target to build if no target is specified?
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To save others a few seconds, and to save them from having to read the manual, here's the short answer. Add this to the top of your make file:
.DEFAULT_GOAL := mytarget
mytarget will now be the target that is run if "make" is executed and no target is specified.
If yo...
Associativity of “in” in Python?
...code: JUMP_IF_FALSE_OR_POP, which shortens the sequence by one instruction from 13 to 12. Cool answer - thanks!!
– Dave
Sep 30 '12 at 20:23
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Is there a good way to attach JavaScript objects to HTML elements?
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From my experience the reason this can be bad is possible memory leaks. There might be an easy way to avoid it, but when I made a design that used this heavily it had many memory leaks. I think you have to be extra careful ...
Difference between two dates in Python
...get the difference between two datetime objects and take the days member.
from datetime import datetime
def days_between(d1, d2):
d1 = datetime.strptime(d1, "%Y-%m-%d")
d2 = datetime.strptime(d2, "%Y-%m-%d")
return abs((d2 - d1).days)
...
PHP + curl, HTTP POST sample code?
...le
curl.cainfo=c:\php\cacert.pem
The latest cacert.pem can be downloaded from the Internet or extracted from your favorite browser. When changing any php.ini related settings remember to restart your webserver.
share
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what is the preferred way to mutate a React state?
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Calling this.setState with a value derived from this.state will have you fall foul of update batching issues. See stackoverflow.com/a/41445812/1998186 which links to a jsfiddle showing the problem you'll get.
– NealeU
Jan 3 '17 ...
Parallel.ForEach vs Task.Factory.StartNew
...so takes into account the number of hardware threads available, saving you from having to work out the optimum number of Tasks to start. Check out Microsoft's Patterns of Parallel Programming article; it's got great explanations of all of this stuff in it.
– Mal Ross
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Set “this” variable easily?
...otype object so every function can use them (since every function inherits from this prototype via prototypal inheritance). These functions are the following:
Function.prototype.call(): This function takes the object which you want to use as this as a first argument. Then the remainder of the argu...
How to pass a user defined argument in scrapy spider
... def parse(self, response)
self.log(self.domain) # system
Taken from the Scrapy doc: http://doc.scrapy.org/en/latest/topics/spiders.html#spider-arguments
Update 2013: Add second argument
Update 2015: Adjust wording
Update 2016: Use newer base class and add super, thanks @Birla
Update ...