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“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
...it in order to avoid some security vulnerabilities or bugs where one would forget to give a value to a variable that will be used later in the script. What PHP does in the case of undeclared variables is issue a very low level error, E_NOTICE, one that is not even reported by default, but the Manual...
What's the (hidden) cost of Scala's lazy val?
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It looks like the compiler arranges for a class-level bitmap int field to flag multiple lazy fields as initialized (or not) and initializes the target field in a synchronized block if the relevant xor of the bitmap indicates it is necessary.
Using:
class Some...
Does python have an equivalent to Java Class.forName()?
... of the class named in that string in Python. In Java, I would use Class.forName().newInstance() . Is there an equivalent in Python?
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What is the formal difference in Scala between braces and parentheses, and when should they be used?
What is the formal difference between passing arguments to functions in parentheses () and in braces {} ?
9 Answers
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`staticmethod` and `abc.abstractmethod`: Will it blend?
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@iraklikhitarishvili Still, that doesn't enforce the subclass's method to be static! You have to duplicate the staticmethod decorator... Is there no way around that?
– étale-cohomology
Mar 11 '16 at 19:12
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How to read data From *.CSV file using javascript?
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NOTE: I concocted this solution before I was reminded about all the "special cases" that can occur in a valid CSV file, like escaped quotes. I'm leaving my answer for those who want something quick and dirty, but I recommend Evan's answer for accuracy.
Thi...
How to make my custom type to work with “range-based for loops”?
...ferent features that C++11 brings. One of my favorites is the "range-based for loops".
8 Answers
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Lua简明教程 - 脚本技术 - 清泛IT论坛，有思想、有深度
...另外，条件表达式中的与或非为分是：and, or, not关键字。for 循环
sum = 0
for i = 1, 100 do
sum = sum + i
end复制代码
从1到100的奇数和
sum = 0
for i = 1, 100, 2 do
sum = sum + i
end复制代码
从100到1的偶数和
sum = 0
for i = 100, 1...
How do I check OS with a preprocessor directive?
...hings based on the operating system on which it gets compiled. I'm looking for something like this:
16 Answers
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C# 5 async CTP: why is internal “state” set to 0 in generated code before EndAwait call?
... from the VB part of the team confirmed that there really is a good reason for it. Many thanks to him - and please visit his blog, which rocks.
The value 0 here is only special because it's not a valid state which you might be in just before the await in a normal case. In particular, it's not a sta...