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Multiple left-hand assignment with JavaScript
...e right most before the left most. so var var1=var2 happens after var3 = 1 and after var2 = var3. it's like var3=1; var2=var3; var var1=var2
– gcb
Jan 29 '13 at 18:51
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do..end vs curly braces for blocks in Ruby
...worker who is actively trying to convince me that I should not use do..end and instead use curly braces for defining multiline blocks in Ruby.
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A semantics for Bash scripts?
...ripts that appear to work. However, I don't really know what's going on, and I was hoping for a more formal introduction to Bash as a programming language. For example: What is the evaluation order? what are the scoping rules? What is the typing discipline, e.g. is everything a string? What is the...
Booleans, conditional operators and autoboxing
...time:
E1: `true ? returnsNull() : false` - boolean (auto-unboxing 2nd operand to boolean)
E2: `true ? null : false` - Boolean (autoboxing of 3rd operand to Boolean)
See Java Language Specification, section 15.25 Conditional Operator ? :
For E1, the types of the 2nd and 3rd operands are Boolean...
How does the Windows Command Interpreter (CMD.EXE) parse scripts?
...ovides good help regarding how to write batch scripts that the Windows Command Interpreter will run.
7 Answers
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How do I put an already-running process under nohup?
I have a process that is already running for a long time and don't want to end it.
11 Answers
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SQL Switch/Case in 'where' clause
...ly below, you formed the SQL incorrectly. I tested mine in SQLServer 2005 and it worked fine.
– Bob Probst
Oct 16 '08 at 0:48
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Is it safe to use -1 to set all bits to true?
...times have surprising behavior because you will have to have the right operand type. Only then you will get the most high value of an unsigned type.
For an example of a possible surprise, consider this one:
unsigned long a = ~0u;
It won't necessarily store a pattern with all bits 1 into a. But ...
What's the difference between lists and tuples?
...cture, lists have order.
Using this distinction makes code more explicit and understandable.
One example would be pairs of page and line number to reference locations in a book, e.g.:
my_location = (42, 11) # page number, line number
You can then use this as a key in a dictionary to store not...
Replace all 0 values to NA
...ays in ?'NULL',
NULL represents the null object in R
which is unique and, I guess, can be seen as the most uninformative and empty object.1 Then it becomes not so surprising that
data.frame(x = c(1, NULL, 2))
# x
# 1 1
# 2 2
That is, R does not reserve any space for this null object.2 Mea...