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XML Schema minOccurs / maxOccurs default values
I'm wondering how the XML Schema specification handles these cases:
4 Answers
4
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What is the difference between IEqualityComparer and IEquatable?
I want to understand the scenarios where IEqualityComparer<T> and IEquatable<T> should be used.
The MSDN documentation for both looks very similar.
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Type Checking: typeof, GetType, or is?
...y_a_dog = new Dog();
Foo(probably_a_dog); // this calls Foo<Animal> and returns "Animal"
Foo<Animal>(probably_a_dog); // this is exactly the same as above
Foo<Dog>(probably_a_dog); // !!! This will not compile. The parameter expects a Dog, you cannot pass in an Animal.
Foo(defini...
Replace one character with another in Bash
...lexity is worse than linear. A small test: x="$(tr -dc 'a-z \n' </dev/urandom | head -c1M)"; time y="$(tr ' ' \\- <<< "$x")"; time z="${x// /-}". With a string length of 1M (=2^20) tr took 0.04s and bash 5.0.11 took 17s. With 2M tr took 0.07s (expected) but bash took 69s (4 times as lon...
Variable number of arguments in C++?
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You probably shouldn't, and you can probably do what you want to do in a safer and simpler way. Technically to use variable number of arguments in C you include stdarg.h. From that you'll get the va_list type as well as three functions that opera...
Python function global variables?
... value of the result of func_A, or (3) to a local variable x with no value and (in the eyes of the compiler) no relation to "some value" or the x in func_A?
– Akshat Shekhar
May 14 '12 at 18:00
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What does “@” mean in Windows batch scripts
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It means not to output the respective command. Compare the following two batch files:
@echo foo
and
echo foo
The former has only foo as output while the latter prints
H:\Stuff>echo foo
foo
(here, at least). As can be seen the command that is run is visib...
PHP memory profiling
...page's memory usage? For example, to see how much memory my data is using, and/or which function calls are allocating the most memory.
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How do I convert an existing callback API to promises?
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Promises have state, they start as pending and can settle to:
fulfilled meaning that the computation completed successfully.
rejected meaning that the computation failed.
Promise returning functions should never throw, they should return rejections instead. Throwi...
Do htmlspecialchars and mysql_real_escape_string keep my PHP code safe from injection?
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When it comes to database queries, always try and use prepared parameterised queries. The mysqli and PDO libraries support this. This is infinitely safer than using escaping functions such as mysql_real_escape_string.
Yes, mysql_real_escape_string is effectively just a ...