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What does |= (ior) do in Python?
...s1 |= s2 # 2
>>> s1.__ior__(s2) # 3
where the final value of s1 is equivalent either by:
an assigned OR operation
an in-place OR operation
an in-place OR operation via special method++
Example
Here we a...
Listening for variable changes in JavaScript
...ve an array of listeners instead of a single one and then instead of just calling this.aListener(val), you would have to loop through all listener functions and call each one passing val. Typically, the method is called addListener instead of registerListener.
– Akira
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Linux: copy and create destination dir if it does not exist
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oops, right. But then, test may be a bash builtin (especially if written as [[ -d "$d" ]]) and mkdir can not ;-)
– Michael Krelin - hacker
Oct 7 '09 at 17:00
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Recursive lambda functions in C++11
... in MSVC, where I have experience with them), it's just that they aren't really compatible with type inference.
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how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
...gsql-control-structures.html, example 40-2 right at the bottom.
That's usually the easiest way. You can do some magic with rules, but it's likely going to be a lot messier. I'd recommend the wrap-in-function approach over that any day.
This works for single row, or few row, values. If you're deali...
Add a property to a JavaScript object using a variable as the name?
...out modifying but it's referenced by other questions that are about dynamically creating objects and so I ended up here and happily benefited from this answer.
– Oliver Lloyd
Oct 29 '16 at 17:40
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Entity Framework: One Database, Multiple DbContexts. Is this a bad idea? [closed]
...y single context in your application can do that. The trick for this is usually one additional context containing all your entities which is used only for database creation. Your real application contexts containing only subsets of your entities must have database initializer set to null.
There are...
MySQL Cannot drop index needed in a foreign key constraint
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You have to drop the foreign key. Foreign keys in MySQL automatically create an index on the table (There was a SO Question on the topic).
ALTER TABLE mytable DROP FOREIGN KEY mytable_ibfk_1 ;
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Format number as fixed width, with leading zeros [duplicate]
...format a number as integer of width 3:
a <- seq(1,101,25)
sprintf("name_%03d", a)
[1] "name_001" "name_026" "name_051" "name_076" "name_101"
Another is formatC and paste:
paste("name", formatC(a, width=3, flag="0"), sep="_")
[1] "name_001" "name_026" "name_051" "name_076" "name_101"
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error C2512: “Foo”: 没有合适的默认构造函数可用 - C/C++ - 清泛网 - 专...
...CLUDE\xmemory0(600): 编译类 模板 成员函数
“void std::allocator<_Ty>::construct(_Ty *)”时
with
[
_Ty=Foo
]
C:\Program Files\Microsoft Visual Studio 11.0\VC\INCLUDE\xmemory0(751): 参见对正在编译的函数
模板 实例化“void s...