大约有 4,700 项符合查询结果（耗时：0.0199秒） [XML]
JavaScript closures vs. anonymous functions
... be of two types:
Local variables (bound variables)
Non-local variables (free variables)
If F has no free variables then it cannot be a closure.
If F has any free variables (which are defined in a parent scope of F) then:
There must be only one parent scope of F to which a free variable is boun...
How do I get currency exchange rates via an API such as Google Finance? [closed]
...
Thanks for all your answers.
Free currencyconverterapi:
Rates updated every 30 min
API key is now required for the free server.
A sample conversion URL is: http://free.currencyconverterapi.com/api/v5/convert?q=EUR_USD&compact=y
For posterity here ...
Easy way to prevent Heroku idling?
In the Heroku free apps the dynos seem to keep idling - my app has very low traffic but it's also not really acceptable in my case that my users have to wait 20+ seconds to spin up a new dyno.
...
Is C++ context-free or context-sensitive?
...only if a given integer is prime.
So I assert that C++ is neither context-free nor context-sensitive.
If you allow arbitrary symbol sequences on both sides of any production, you produce an Type-0 grammar ("unrestricted") in the Chomsky hierarchy, which is more powerful than a context-sensitive gr...
What is “point free” style (in Functional Programming)?
A phrase that I've noticed recently is the concept of "point free" style...
5 Answers
...
When you exit a C application, is the malloc-ed memory automatically freed?
...ting system. The majority of modern (and all major) operating systems will free memory not freed by the program when it ends.
Relying on this is bad practice and it is better to free it explicitly. The issue isn't just that your code looks bad. You may decide you want to integrate your small progra...
Heroku free account limited?
Currently, I am running wordpress as my blog engine on free hosting, but I'm planning to move to use git-based blog engine(Jekyll, Toto) on Ruby platform. Then I see Heroku provides free account features, but I don't see any detail on bandwidth, disk spaces, requests?
...
Get free disk space
Given each of the inputs below, I'd like to get free space on that location. Something like
13 Answers
...
Are memory leaks ever ok? [closed]
...personally go with exactly the same answer, there are programs that hardly free memory at all. The reason is that they are a) intended to run on OSes that free memory, and b) designed not to run very long. Rare constraints for a program indeed, but I accept this as perfectly valid.
...
Efficiency of premature return in a function
...th resource allocation, and then error checking with a potential resulting freeing of resources, the picture might change.
Consider the naive approach beginners might take:
int func(..some parameters...) {
res_a a = allocate_resource_a();
if (!a) {
return 1;
}
res_b b = allocate_resour...