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What are the differences between Rust's `String` and `str`?
... use String if you need owned string data (like passing strings to other threads, or building them at runtime), and use &str if you only need a view of a string.
This is identical to the relationship between a vector Vec<T> and a slice &[T], and is similar to the relationship between b...
How to sort a dataframe by multiple column(s)
... use the arrange() function from plyr as Hadley pointed out in the above thread:
library(plyr)
arrange(dd,desc(z),b)
Benchmarks: Note that I loaded each package in a new R session since there were a lot of conflicts. In particular loading the doBy package causes sort to return "The following o...
Using an ORM or plain SQL? [closed]
...
I say plain SQL for Reads, ORM for CUD.
Performance is something I'm always concerned about, specially in web applications, but also code maintainability and readability. To address these issues I wrote SqlBuilder.
...
AngularJS - Access to child scope
...r solutions:
Define properties in parents and access them from children (read the link above)
Use a service to share state
Pass data through events. $emit sends events upwards to parents until the root scope and $broadcast dispatches events downwards. This might help you to keep things semanticall...
py2exe - generate single executable file
... excludes=['_ssl', # Exclude _ssl
'pyreadline', 'difflib', 'doctest', 'locale',
'optparse', 'pickle', 'calendar', 'pbd', 'unittest', 'inspect'], # Exclude standard library
dll_excludes=['msvcr71.dll', 'w9x...
Ruby: kind_of? vs. instance_of? vs. is_a?
...
It just reads better sometimes. Think @honda.kind_of? Car and @person.is_a? Administrator, Ruby's all about the aesthetics. In fact, notice the grammatical error... with active support you can write @person.is_an? Administrator :)......
jQuery Ajax POST example with PHP
....always().
Note: Remember that the above snippet has to be done after DOM ready, so you should put it inside a $(document).ready() handler (or use the $() shorthand).
Tip: You can chain the callback handlers like this: $.ajax().done().fail().always();
PHP (that is, form.php):
// You can access t...
How can I convert this foreach code to Parallel.ForEach?
...
string[] lines = File.ReadAllLines(txtProxyListPath.Text);
List<string> list_lines = new List<string>(lines);
Parallel.ForEach(list_lines, line =>
{
//Your stuff
});
...
Call a function with argument list in python
...ctions or the function calls) is simply to alter the line
func(args)
to read
func(*args)
This tells Python to take the list given (in this case, args) and pass its contents to the function as positional arguments.
This trick works on both "sides" of the function call, so a function defined l...
Postgres and Indexes on Foreign Keys and Primary Keys
... @Matthias - Ah, got it. Thanks. Yeah, I obviously didn't take time to read through the code. It wasn't critical enough to bother. The OP could've mentioned the limitations. Maybe I'll check it out again sometime.
– juanitogan
Mar 31 '17 at 1:23
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