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How do I get around type erasure on Scala? Or, why can't I get the type parameter of my collections?
...les above, doesn't the unchecked part in front of the guard condition do a cast? Wouldn't you get a class cast exception when going through the matches on the first object that cant' be cast to a string?
– Toby
Aug 28 '15 at 10:32
...
Convert char to int in C and C++
... code, you can write
char a = 'a';
int ia = (int)a;
/* note that the int cast is not necessary -- int ia = a would suffice */
to convert the character '0' -> 0, '1' -> 1, etc, you can write
char a = '4';
int ia = a - '0';
/* check here if ia is bounded by 0 and 9 */
Explanation:
a - '0'...
Does the 'mutable' keyword have any purpose other than allowing the variable to be modified by a con
....
Without the mutable keyword you will eventually be forced to use const_cast to handle the various useful special cases it allows (caching, ref counting, debug data, etc.). Unfortunately const_cast is significantly more destructive than mutable because it forces the API client to destroy the cons...
Custom global Application class breaks with “android.app.Application cannot be cast to”
...y. I have this added to my manifest. However, it is still giving me a ClassCastException
– Somu
Jul 31 '15 at 19:45
14
...
What's the strangest corner case you've seen in C# or .NET? [closed]
... All the methods are overridden, except GetType() which can't be; so it is cast (boxed) to object (and hence to null) to call object.GetType()... which calls on null ;-p
Update: the plot thickens... Ayende Rahien threw down a similar challenge on his blog, but with a where T : class, new():
priv...
Undefined reference to static class member
...question. The second part is much more interesting: Why does adding a NOP cast make it work without requiring the external declaration?
– Brent Bradburn
Feb 1 '11 at 0:48
...
How can I easily convert DataReader to List? [duplicate]
... writing an extension method for this:
public static IEnumerable<T> Select<T>(this IDataReader reader,
Func<IDataReader, T> projection)
{
while (reader.Read())
{
yield return projection(reader);
}
}
You can then use LINQ...
Java switch statement: Constant expression required, but it IS constant
...ice.Choice1;
switch(ch) {
case Choice1:
System.out.println("Choice1 selected");
break;
case Choice2:
System.out.println("Choice2 selected");
break;
case Choice3:
System.out.println("Choice3 selected");
break;
}
}
}
Source:
Switch statement with enum
...
Sql query to insert datetime in SQL Server
...clare @LangID smallint
declare @Alias sysname
declare @MaxLangID smallint
select @MaxLangID = max(langid) from sys.syslanguages
set @LangID = 0
while @LangID <= @MaxLangID
begin
select @Alias = alias
from sys.syslanguages
where langid = @LangID
if @Alias is not null
begin...
What is a method group in C#?
...
Also, if you are using LINQ, you can apparently do something like myList.Select(methodGroup).
So, for example, I have:
private string DoSomethingToMyString(string input)
{
// blah
}
Instead of explicitly stating the variable to be used like this:
public List<string> GetStringStuff()...