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Constructor function vs Factory functions
...an't forget new with a class constructor, or the constructor will throw an error.
If you do the instanceof check, it leaves ambiguity as to whether or not new is required. In my opinion, it shouldn't be. You've effectively short circuited the new requirement, which means you could erase drawback #1....
How to calculate date difference in JavaScript?
... x0 = new Date(d0);
var x1 = new Date(d1);
// Set to noon - avoid DST errors
x0.setHours(12,0,0);
x1.setHours(12,0,0);
// Round to remove daylight saving errors
return Math.round( (x1 - x0) / msPerDay );
}
This can be more concise:
/* Return number of days between d0 and d1.
*...
Parsing a JSON string in Ruby
...ny cases you want to wrap JSON.parse within a rescue block for JSON::ParserError.
– johnml
Jun 10 '14 at 10:48
JSON.pa...
Rails 3 - can't install pg gem
...
As stated in your error log you need to pass in the path to the pg_config. Try to install the gem using:
gem install pg -- --with-pg-config= 'PATH_TO_YOUR_PG_CONFIG'
If you are not sure where your pg_config is, and assuming you are on Linux...
How should one use std::optional?
...archy, instead of passing around some "phantom" value "assumed" to have a "error" meaning.
– Luis Machuca
Oct 3 '13 at 16:35
1
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Multiple arguments vs. options object
...xplicit documentation to specify intent, but it also leaves room for vague errors.
What if a developer modifies param1 in bar()? How long do you think it would take looking through a codebase of sufficident size to catch this?
Admittedly, this is example is slightly disingenuous because it assumes d...
How to sort with a lambda?
...in place of binding an instance method. However, the code above yields the error:
3 Answers
...
How to reverse a singly linked list using only two pointers?
...
I'm not sure about 'obvious errors' in the original. Design-wise, not passing the head of the list in and not returning the new head is a bad idea. The only bug, though, is the last line in the reverse() function should be setting first, I believe. O...
How to schedule a periodic task in Java?
...sk process
} catch (Exception ex) {
System.out.println("error running thread " + ex.getMessage());
}
}
}
then in main class you instantiate the task and run it periodically started by a specified date:
public void runTask() {
Calendar calendar = Calendar.ge...
What is the Java ?: operator called and what does it do?
...th branches must lead to methods with return values:
It is a compile-time error for either the second or the third operand expression to be an invocation of a void method.
In fact, by the grammar of expression statements (§14.8), it is not permitted for a conditional expression to appear in any co...