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Why does pattern matching in Scala not work with variables?
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What you're looking for is a stable identifier. In Scala, these must either start with an uppercase letter, or be surrounded by backticks.
Both of these would be solutions to your problem:
def mMatch(s: String) = {
val target: String = "a"
s match {
case `target` => println...
difference between primary key and unique key
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Primary Key:
There can only be one primary key in a table
In some DBMS it cannot be NULL - e.g. MySQL adds NOT NULL
Primary Key is a unique key identifier of the record
Unique Key:
Can be more than one unique key in one table
Unique key can have NULL values
It can be a candidate key
Unique k...
How to read from standard input in the console?
... to read standard input from the command line, but my attempts have ended with the program exiting before I'm prompted for input. I'm looking for the equivalent of Console.ReadLine() in C#.
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Django: Set foreign key using integer?
...= 4
employee.save()
ForeignKey fields store their value in an attribute with _id at the end, which you can access directly to avoid visiting the database.
The _id version of a ForeignKey is a particularly useful aspect of Django, one that everyone should know and use from time to time when approp...
What are bitwise shift (bit-shift) operators and how do they work?
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The bit shifting operators do exactly what their name implies. They shift bits. Here's a brief (or not-so-brief) introduction to the different shift operators.
The Operators
>> is the arithmetic (or signed) right shift o...
https URL with token parameter : how secure is it?
On our site, we provide to users a simulation based on their private information (given through a form). We would like to allow them to get back on their simulation results later, but without forcing them to create a login/password account.
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@try - catch block in Objective-C
Why doesn't @try block work?
It crashed the app, but it was supposed to be caught by the @try block.
3 Answers
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Scala: join an iterable of strings
How do I "join" an iterable of strings by another string in Scala?
1 Answer
1
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insert multiple rows via a php array into mysql
...aset into a MySQL table via PHP using insert commands and I'm wondering if its possible to insert approximately 1000 rows at a time via a query other than appending each value on the end of a mile long string and then executing it. I am using the CodeIgniter framework so its functions are also avail...
What's an appropriate HTTP status code to return by a REST API service for a validation failure?
...instance if the URI is supposed to have an ISO-8601 date and you find that it's in the wrong format or refers to February 31st, then you would return an HTTP 400. Ditto if you expect well-formed XML in an entity body and it fails to parse.
(1/2016): Over the last five years WebDAV's more specific ...