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Get type of all variables
...R, I'd like to retrieve a list of global variables at the end of my script and iterate over them. Here is my code
6 Answers...
Does Java 8 provide a good way to repeat a value or function?
...- 1)
.forEach(System.out::println);
Or build a custom iteration and limit the size of the iteration:
IntStream.iterate(1, i -> i + 2)
.limit(8)
.forEach(System.out::println);
share
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How to copy a selection to the OS X clipboard
...this might not work for you, but if you have Vim-version 7.4 then it does (and sometimes you don't even have to do the whole "+y ). And you check this by just writing >vim in the terminal and then the version-number is when you start it up.
– Zeth
Sep 9 '1...
Understanding dict.copy() - shallow or deep?
... 3, 4, 5]}, {1: [1, 2, 3, 4]})
So:
b = a: Reference assignment, Make a and b points to the same object.
b = a.copy(): Shallow copying, a and b will become two isolated objects, but their contents still share the same reference
b = copy.deepcopy(a): Deep copying, a and b's structure and conte...
Best practices for in-app database migration for Sqlite
I am using sqlite for my iphone and I anticipate the database schema might change over time. What are the gotchas, naming conventions and things to watch out for to do a successful migration each time?
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sort object properties and JSON.stringify
My application has a large array of objects, which I stringify and save them to the disk. Unfortunately, when the objects in the array are manipulated, and sometimes replaced, the properties on the objects are listed in different orders (their creation order?). When I do JSON.stringify() on the arr...
Intelligent point label placement in R
...ints (or other objects in the plot, but I see that this is much harder to handle).
7 Answers
...
Set cURL to use local virtual hosts
... applies, but simply pretends the DNS lookup returned the data in your command-line option. It works just like /etc/hosts should.
Note --resolve takes a port number, so for HTTPS you would use
curl --resolve 'yada.com:443:127.0.0.1' https://yada.com/something
...
How to concatenate twice with the C preprocessor and expand a macro as in “arg ## _ ## MACRO”?
...
Standard C Preprocessor
$ cat xx.c
#define VARIABLE 3
#define PASTER(x,y) x ## _ ## y
#define EVALUATOR(x,y) PASTER(x,y)
#define NAME(fun) EVALUATOR(fun, VARIABLE)
extern void NAME(mine)(char *x);
$ gcc -E xx.c
# 1 "xx.c"
# ...
Difference between dispatch_async and dispatch_sync on serial queue?
...k is finished whereas dispatch_async return after it is added to the queue and may not finished.
for this code
dispatch_async(_serialQueue, ^{ printf("1"); });
printf("2");
dispatch_async(_serialQueue, ^{ printf("3"); });
printf("4");
It may print 2413 or 2143 or 1234 but 1 always before 3
for ...