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'is' versus try cast with null check
...// only one cast
if (myObjRef != null)
{
// myObjRef is already MyType and doesn't need to be cast again
...
}
C# 7.0 supports a more compact syntax using pattern matching:
if (myObj.myProp is MyType myObjRef)
{
...
}
...
Command not found error in Bash variable assignment
...d your '=' sign.
When you write:
STR = "foo"
bash tries to run a command named STR with 2 arguments (the strings '=' and 'foo')
When you write:
STR =foo
bash tries to run a command named STR with 1 argument (the string '=foo')
When you write:
STR= foo
bash tries to run the command foo ...
Batch file: Find if substring is in string (not in a file)
...
Yes, you can use substitutions and check against the original string:
if not x%str1:bcd=%==x%str1% echo It contains bcd
The %str1:bcd=% bit will replace a bcd in str1 with an empty string, making it different from the original.
If the original didn't c...
How to make inline functions in C#
...ored
{
Console.WriteLine("Hello world!");
}
Lambdas are new in C# 3.0 and come in two flavours.
Expression lambdas:
Func<int, int, int> add = (int x, int y) => x + y; // or...
Func<int, int, int> add = (x, y) => x + y; // types are inferred by the compiler
Statement lambda...
How to show “Done” button on iPhone number pad
...
@BenPotter You would set the barTint for the bar color and tint color for the text. You could also create the UIBarButton items out side of the intializer and set the color for them explicitly there.
– ocross
May 6 '14 at 23:55
...
What is a memory fence?
...are concept. In higher level languages we are used to dealing with mutexes and semaphores - these may well be implemented using memory fences at the low level and explicit use of memory barriers are not necessary. Use of memory barriers requires a careful study of the hardware architecture and more ...
What does “SyntaxError: Missing parentheses in call to 'print'” mean in Python?
..."Missing parentheses in call to print" case is a compile time syntax error and hence has access to the raw source code, it's able to include the full text on the rest of the line in the suggested replacement. However, it doesn't currently try to work out the appropriate quotes to place around that e...
Is it possible to await an event instead of another async method?
...something like that. It just means “you can use await in this method”. And in this case, blocking inside GetResults() would actually block the UI thread.
– svick
Oct 12 '12 at 12:24
...
Difference between RegisterStartupScript and RegisterClientScriptBlock?
Is the only difference between the RegisterStartupScript and the RegisterClientScriptBlock is that RegisterStartupScript puts the javascript before the closing </form> tag of the page and RegisterClientScriptBlock puts it right after the starting <form> tag of the page?
...
Can git automatically switch between spaces and tabs?
...butes which contains:
*.py filter=tabspace
Linux/Unix
Now run the commands:
git config --global filter.tabspace.smudge 'unexpand --tabs=4 --first-only'
git config --global filter.tabspace.clean 'expand --tabs=4 --initial'
OS X
First install coreutils with brew:
brew install coreutils
Now...