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How to change the foreign key referential action? (behavior)
... means that if you delete a row from the parent table (Users in this case) all referencing rows from the child table (UserDetails) are also deleted.
– edruid
Jan 11 '18 at 14:20
1
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What is the strict aliasing rule?
...n(void)
{
// Get a 32-bit buffer from the system
uint32_t* buff = malloc(sizeof(Msg));
// Alias that buffer through message
Msg* msg = (Msg*)(buff);
// Send a bunch of messages
for (int i = 0; i < 10; ++i)
{
msg->a = i;
msg->b = i+1;...
How do I remove duplicate items from an array in Perl?
...is as demonstrated in perlfaq4:
sub uniq {
my %seen;
grep !$seen{$_}++, @_;
}
my @array = qw(one two three two three);
my @filtered = uniq(@array);
print "@filtered\n";
Outputs:
one two three
If you want to use a module, try the uniq function from List::MoreUtils
...
What does static_assert do, and what would you use it for?
...fined (as one would expect in a C++ library).
Contrast with having to actually compile SomeLibrary and your code, link everything, and run the executable only then to find out that you spent 30 minutes compiling an incompatible version of SomeLibrary.
@Arak, in response to your comment: yes, you ...
How can I use if/else in a dictionary comprehension?
...
@Marcin's answer covers it all, but just in case someone wants to see an actual example, I add two below:
Let's say you have the following dictionary of sets
d = {'key1': {'a', 'b', 'c'}, 'key2': {'foo', 'bar'}, 'key3': {'so', 'sad'}}
and you want ...
What is the best algorithm for overriding GetHashCode?
...hroughout the .NET base class libraries. Implementing it properly is especially important to find items quickly in a collection or when determining equality.
...
Defining a function with multiple implicit arguments in Scala
...
They must all go in one parameter list, and this list must be the last one.
def myfun(arg:String)(implicit p1: String, p2:Int)={}
share
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Accessing nested JavaScript objects and arays by string path
...
great stuff; using the lodash library, one can also do: _.get(object, nestedPropertyString);
– ian
Aug 13 '15 at 12:49
17
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What does the “===” operator do in Ruby? [duplicate]
...
Just like with every other method in Ruby (or actually pretty much any object-oriented language),
a === b
means whatever the author of a's class wants it to mean.
However, if you don't want to confuse the heck out of your colleagues, the convention is that === is the cas...
Displaying better error message than “No JSON object could be decoded”
... also up on PYPI: https://pypi.python.org/pypi/rson/0.9 so you can use easy_install or pip to get it.
for the example given by tom:
>>> rson.loads('[1,2,]')
...
rson.base.tokenizer.RSONDecodeError: Unexpected trailing comma: line 1, column 6, text ']'
RSON is a designed to be a superset...