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Creating an empty file in Ruby: “touch” equivalent?
...
If you are worried about file handles:
File.open("foo.txt", "w") {}
From the docs:
If the optional code block is given, it will be passed the opened file
as an argument, and the File object will automatically be clos...
Adding a new value to an existing ENUM Type
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NOTE if you're using PostgreSQL 9.1 or later, and you are ok with making changes outside of a transaction, see this answer for a simpler approach.
I had the same problem few days ago and found this post. So my answer can be hel...
C++STL容器使用经验总结 - C/C++ - 清泛网 - 专注C/C++及内核技术
...对象：
如果容器是vector、string或deque，则使用erase-remove_if习惯用法。
如果容器是list，则使用list::remove_if。
如果容器是一个标准关联容器，则使用remove_copy_if和swap，或者写一个循环遍历容器的元素，记住当把迭代器传给erase时...
list_display - boolean icons for methods
When defining the list_display array for a ModelAdmin class, if a BooleanField or NullBooleanField is given the UI will use nice looking icons instead of True/False text in the column. If a method that returns a boolean is given, however, it simply prints out True/False.
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Break out of a While…Wend loop
...p)
Change to a Do loop instead:
Do While True
count = count + 1
If count = 10 Then
Exit Do
End If
Loop
Or for looping a set number of times:
for count = 1 to 10
msgbox count
next
(Exit For can be used above to exit prematurely)
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How to filter None's out of List[Option]?
If I have a List[Option[A]] in Scala, what is the idiomatic way to filter out the None values?
3 Answers
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How to force 'cp' to overwrite directory instead of creating another one inside?
...-- foo
|-- a
`-- b
2 directories, 4 files
You can see the clear difference when you use -v for Verbose.
When you use just -R option.
$ cp -Rv foo/ bar/
`foo/' -> `bar/foo'
`foo/b' -> `bar/foo/b'
`foo/a' -> `bar/foo/a'
$ tree
|-- bar
| |-- a
| |-- b
| `-- foo
| |...
How do I jump out of a foreach loop in C#?
How do I break out of a foreach loop in C# if one of the elements meets the requirement?
11 Answers
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Can git operate in “silent mode”?
...on jobs:
quiet_git() {
stdout=$(tempfile)
stderr=$(tempfile)
if ! git "$@" </dev/null >$stdout 2>$stderr; then
cat $stderr >&2
rm -f $stdout $stderr
exit 1
fi
rm -f $stdout $stderr
}
This will suppress stdout and stderr, unless the git...
Difference between hard wrap and soft wrap?
... that a number of them refer to a "soft" versus "hard" wrap. What is the difference? I can't seem to find the answer by searching.
...