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Case objects vs Enumerations in Scala
... deal with an Option[Currency] type that would clearly indicate there is really a matching problem and "encourage" the user of the API to sort it out him/herself.
To follow up on the other answers here, the main drawbacks of case objects over Enumerations are:
Can't iterate over all instances of t...
I want to get the type of a variable at runtime
...that comparison return true, but it would require a few book chapters to really cover TypeTag, so I'll stop here.
Finally, maybe you don't care about the type of the variable at all. Maybe you just want to know what is the class of a value, in which case the answer is rather simple:
val x = 5
x.ge...
Difference between \w and \b regular expression meta characters
...chor like the caret and the dollar sign. It matches at a position that is called a "word boundary". This match is zero-length.
There are three different positions that qualify as word boundaries:
Before the first character in the string, if the first character is
a word character.
After the last ...
Share cookie between subdomain and domain
...fy the domain as .mydomain.com (with the leading dot) in the cookie that all subdomains can share a cookie.
7 Answers
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Rounded table corners CSS only
... only, you get 2px thick borders, which is ugly. Rather have no borders at all.
– Vishal Shah
Feb 8 '11 at 11:27
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Runtime vs. Compile time
...n compile time and run time is an example of what pointy-headed theorists call the phase distinction. It is one of the hardest concepts to learn, especially for people without much background in programming languages. To approach this problem, I find it helpful to ask
What invariants does the pr...
Django set default form values
...ch is explained here
You have two options either populate the value when calling form constructor:
form = JournalForm(initial={'tank': 123})
or set the value in the form definition:
tank = forms.IntegerField(widget=forms.HiddenInput(), initial=123)
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Why are empty catch blocks a bad idea? [closed]
...-catch , which people (including Jon Skeet) say empty catch blocks are a really bad idea? Why this? Is there no situation where an empty catch is not a wrong design decision?
...
Loop through properties in JavaScript object with Lodash
.../lodash.com/docs#forOwn
Note that forOwn checks hasOwnProperty, as you usually need to do when looping over an object's properties. forIn does not do this check.
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JavaScript equivalent of PHP's in_array()
.../ alerts 'ph' was found
// alerts 'o' was found
Note that I intentionally did not extend the Array prototype as it is generally a bad idea to do so.
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