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How to map and remove nil values in Ruby
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Ruby 2.7 is introducing filter_map for this exact purpose. It's idiomatic and performant, and I'd expect it to become the norm very soon.
For example:
numbers = [1, 2, 5, 8, 10, 13]
enum.filter_map { |i| i * 2 if i.even? }
# => [4, 16, 20]
In your case, as the block evaluates to falsey, simp...
Any way to select without causing locking in MySQL?
...rver you would do the following:
SELECT * FROM TABLE_NAME WITH (nolock)
and the MYSQL equivalent is
SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED ;
SELECT * FROM TABLE_NAME ;
SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ ;
EDIT
Michael Mior suggested the following (from t...
Visual Studio “Could not copy” … during build
...d success by doing the following:
Closing Visual Studio
Deleting the bin and obj folders, and
Reopening Visual Studio.
This "bug" has existed since Visual Studio 2003.
Finally, I have also found that I can often overcome this problem by simply renaming the executable file and then deleting it.
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When should std::move be used on a function return value? [duplicate]
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met save for the fact that the source object is a function parameter,
and the object to be copied is designated by an lvalue, overload
resolution to select the constructor for the copy is first performed as
if the object were designated by an rvalue.
return foo; is a case of NRVO, so cop...
How do I add a foreign key to an existing SQLite table?
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SQLite doesn't support the ADD CONSTRAINT variant of the ALTER TABLE command (sqlite.org: SQL Features That SQLite Does Not Implement).
Therefore, the only way to add a foreign key in sqlite 3.6.1 is during CREATE TABLE as follows:
CREATE TABLE child (
id INTEGER PRIMARY KEY,
...
How to replace a string in multiple files in linux command line
....bak 's/foo/bar/g' *.xx moves all .xx files to the equivalent .xx.bak name and then generates the .xx files with the foo→bar substitution.
– Anaphory
Oct 4 '14 at 22:35
26
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What is java interface equivalent in Ruby?
Can we expose interfaces in Ruby like we do in java and enforce the Ruby modules or classes to implement the methods defined by interface.
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Why are we not to throw these exceptions?
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Exception is the base type for all exceptions, and as such terribly unspecific. You shouldn’t ever throw this exception because it simply does not contain any useful information. Calling code catching for exceptions couldn’t disambiguate the intentionally thrown excep...
How to turn on/off ReactJS 'development mode'?
...he other answer assumes you are using external pre-built files from react, and while correct that is not how most folks are going to or should consume React as a package. Moreover, at this point most every React library and package also relies on the same convention to toggle dev time helpers off du...
Why is processing a sorted array faster than processing an unsorted array?
...e long distance or radio communication.
You are the operator of a junction and you hear a train coming. You have no idea which way it is supposed to go. You stop the train to ask the driver which direction they want. And then you set the switch appropriately.
Trains are heavy and have a lot of inert...