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Why is conversion from string constant to 'char*' valid in C but invalid in C++
...ion has been removed, an explicit conversion still works, so you can add a cast. I would not, however, consider this "fixing" the code.
Truly fixing the code requires changing the type of the pointer to the correct type:
char const *p = "abc"; // valid and safe in either C or C++.
As to why it w...
How to use Class in Java?
...is overriding the T declared at Class level;
//So There is no ClassCastException though a is not the type of T declared at MyClass<T>.
private <T> T myMethod1(Object a){
return (T) a;
}
//Runtime ClassCastException will be thrown if a is ...
Why should I care that Java doesn't have reified generics?
...
Type safety comes to mind. Downcasting to a parametrized type will always be unsafe without reified generics:
List<String> myFriends = new ArrayList();
myFriends.add("Alice");
getSession().put("friends", myFriends);
// later, elsewhere
List<Frien...
How do I split a string so I can access item x?
...
)
returns table
AS
return (
with tokens(p, a, b) AS (
select
cast(1 as bigint),
cast(1 as bigint),
charindex(@separator, @str)
union all
select
p + 1,
b + 1,
charindex(@separator, @str, b + 1)
from tokens
where b > 0
)
sele...
What is a handle in C++?
...ss HANDLE around as an opaque value.
In the code that uses the object, it casts the pointer to a real structure type and uses it:
int doSomething(HANDLE s, int a, int b) {
Something* something = reinterpret_cast<Something*>(s);
return something->doit(a, b);
}
Or it uses it a...
Why can I pass 1 as a short, but not the int variable i?
...soft.com/en-us/library/ybs77ex4(v=vs.71).aspx
As this page says, implicit casts from a bigger data type to short are only allowed for literals. The compiler can tell when a literal is out of range, but not otherwise, so it needs reassurance that you've avoided an out-of-range error in your program ...
Android Center text on canvas
...
And probably best casting _text.Length to a float as it obviously won't work for odd text lengths.
– paj7777
Apr 8 '13 at 9:44
...
How to get the number of Characters in a String?
...en adds in the comments:
Actually you can do len() over runes by just type casting.
len([]rune("世界")) will print 2. At leats in Go 1.3.
And with CL 108985 (May 2018, for Go 1.11), len([]rune(string)) is now optimized. (Fixes issue 24923)
The compiler detects len([]rune(string)) pattern automati...
.toArray(new MyClass[0]) or .toArray(new MyClass[myList.size()])?
...t it is not created. Additionally, using the zero-length object results in casting(s) within the toArray() - method.
See the source of ArrayList.toArray():
public <T> T[] toArray(T[] a) {
if (a.length < size)
// Make a new array of a's runtime type, but my contents:
re...
Providing a default value for an Optional in Swift?
... {
return defaultValue
}
}
}
however the need to cast value as T is an ugly hack. Ideally, there should be a way to assert that T is the same as the type contained in the Optional. As it stands, type inferencing sets T based on the parameter given to getOrElse, and then fai...