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Why does pattern matching in Scala not work with variables?
...sense that the default behaviour is for lowercase patterns to be variables and not stable identifiers. Only when you see something beginning with upper case, or in back ticks, do you need to be aware that it comes from the surrounding scope.
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How to check if object (variable) is defined in R?
...een created by a queuing system. These can possibly be addressed with "ls" and its argument "pattern" that expects a regular expression.
The "exists" function could be reimplemented that way as
exists <-function(variablename) {
#print(ls(env=globalenv()))
return(1==length(ls(pattern=paste...
How to access parameters in a RESTful POST method
...a JSON object instead of a string. Jersey uses JAXB to support marshaling and unmarshaling JSON objects (see the jersey docs for details). Create a class like:
@XmlRootElement
public class MyJaxBean {
@XmlElement public String param1;
@XmlElement public String param2;
}
Then your @POST ...
Why does Assert.AreEqual(T obj1, Tobj2) fail with identical byte arrays
...ls tests using the Equals method, which by default uses reference equality and, since they are different objects, they are not equal. You'll want to compare each byte in the array and verify that they are equal. One way to do this is convert them to something that implements ICollection and use Co...
Prevent row names to be written to file when using write.csv
Commands:
2 Answers
2
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How to sort my paws?
...nt experiment runs stored as ascii arrays. Rather than try to copy-paste stand-alone code examples into this question, here's a bitbucket mercurial repository with full, stand-alone code. You can clone it with
hg clone https://joferkington@bitbucket.org/joferkington/paw-analysis
Overview
There...
Why does “return list.sort()” return None, not the list?
... l = sorted(l.append('2')) (I just added semi-colon so you could cut/paste and run)
– JGFMK
May 30 '18 at 9:54
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Is there a Python equivalent of the C# null-coalescing operator?
...ator does not return only True or False. Instead, it returns the first operand if the first operand evaluates to true, and it returns the second operand if the first operand evaluates to false.
In this case, the expression x or y returns x if it is True or evaluates to true when converted to boolea...
Does MySQL ignore null values on unique constraints?
...sult:
x
NULL
NULL
1
This is not true for all databases. SQL Server 2005 and older, for example, only allows a single NULL value in a column that has a unique constraint.
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LINQ OrderBy versus ThenBy
.....) allows you to build a single composite comparison for any two objects, and then sort the sequence once using that composite comparison. That's almost certainly what you want.
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