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Why is sizeof considered an operator?
...operator rather than a function. For instance:
union foo {
int i;
char c[sizeof(int)];
};
Syntactically if it weren't an operator then it would have to be a preprocessor macro since functions can't take types as arguments. That would be a difficult macro to implement since sizeof can take...
Serializing object that contains cyclic object value
...
Use the second parameter of stringify, the replacer function, to exclude already serialized objects:
var seen = [];
JSON.stringify(obj, function(key, val) {
if (val != null && typeof val == "object") {
if (seen.indexOf(val) >= 0)...
Changing every value in a hash in Ruby
...
If you want the actual strings themselves to mutate in place (possibly and desirably affecting other references to the same string objects):
# Two ways to achieve the same result (any Ruby version)
my_hash.each{ |_,str| str.gsub! /^|$/, '%' }
my_h...
Writing string to a file on a new line every time
I want to append a newline to my string every time I call file.write() . What's the easiest way to do this in Python?
10 A...
What is a NullPointerException, and how do I fix it?
...your code can help avoid null pointer exception. eg when checking an input string with a constant string you should start with the constant string like here: if ("SomeString".equals(inputString)) {} //even if inputString is null no exception is thrown. So there are a bunch of things that you can do ...
Does C# have extension properties?
...t syntactic sugar adding a possibility to define an extended property like string Data(this MyClass instance) as an alias for extension method string GetData(this MyClass instance) as it stores data into the class.
I hope that C#7 will provide a full featured extension everything (properties and fi...
Insert results of a stored procedure into a temporary table
... You don't need a linked server, but you would need to get the connection string right...and also, specify the full path to the stored procedure including the database name and the sp's owner.
– MartW
Aug 11 '09 at 12:30
...
Difference between clustered and nonclustered index [duplicate]
... every row in your table. This can be anything, really - an INT, a GUID, a string - pick what makes most sense for your scenario.
2) the clustering key (the column or columns that define the "clustered index" on the table) - this is a physical storage-related thing, and here, a small, stable, ever-...
What's the difference between a single precision and double precision floating point operation?
...s 32 bits, its double-precision counterpart will be 64 bits long.
The extra bits increase not only the precision but also the range of magnitudes that can be represented.
The exact amount by which the precision and range of magnitudes are increased depends on what format the program is using ...
What are the “standard unambiguous date” formats for string-to-date conversion in R?
...
This is documented behavior. From ?as.Date:
format: A character string. If not specified, it will try
'"%Y-%m-%d"' then '"%Y/%m/%d"' on the first non-'NA' element,
and give an error if neither works.
as.Date("01 Jan 2000") yields an error because the format isn'...