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How can I return NULL from a generic method in C#?
...ce))
Restrict T to be a reference type with the where T : class constraint and then return null as normal
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PG undefinedtable error relation users does not exist
...llowing:
rake db:reset
The rake db:reset task will drop the database and set it up again. This is functionally equivalent to rake db:drop db:setup.
This is not the same as running all the migrations. It will only use the
contents of the current schema.rb file. If a migration can't be ro...
What is ViewModel in MVC?
I am new to ASP.NET MVC. I have a problem with understanding the purpose of a ViewModel.
14 Answers
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Is there a Unix utility to prepend timestamps to stdin?
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Could try using awk:
<command> | awk '{ print strftime("%Y-%m-%d %H:%M:%S"), $0; fflush(); }'
You may need to make sure that <command> produces line buffered output, i.e. it flushes its output stream after each line; the timestamp awk adds ...
Turning multi-line string into single comma-separated
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You can use awk and sed:
awk -vORS=, '{ print $2 }' file.txt | sed 's/,$/\n/'
Or if you want to use a pipe:
echo "data" | awk -vORS=, '{ print $2 }' | sed 's/,$/\n/'
To break it down:
awk is great at handling data broken down into fi...
How to repeat a string a variable number of times in C++?
... @Brent The OP asked for both - "'n' spaces (or any string)", and then goes on to demonstrate their intent with a single period as the string. English is not many people's first language so you sometimes need to guess their exact requirements and when analysed, the question is really as...
Set a default font for whole iOS app?
...c.).
Remember you'll need to put the UIAppFonts value in your info.plist and include the name of the font you're including.
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How to convert an int value to string in Go?
...tionality in. The creators of Go are all deeply embedded in that heritage and feel entirely comfortable with these names.
– Bryan
Sep 29 '16 at 10:15
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How do I print to the debug output window in a Win32 app?
...t window, but I can't for the life of me work out how. I've tried 'printf' and 'cout
9 Answers
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What is the simplest SQL Query to find the second largest value?
... produce the correct second largest value while if you used the top 2 desc and min approach, you may get the largest value instead.
– Pankaj Sharma
Apr 1 '13 at 19:22
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