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Circular (or cyclic) imports in Python
...
If you do import foo (inside bar.py) and import bar (inside foo.py), it will work fine. By the time anything actually runs, both modules will be fully loaded and will have references to each other.
The problem is when instead you do from foo ...
List changes unexpectedly after assignment. How do I clone or copy it to prevent this?
...-needing method, but sometimes unavoidable.
Example:
import copy
class Foo(object):
def __init__(self, val):
self.val = val
def __repr__(self):
return 'Foo({!r})'.format(self.val)
foo = Foo(1)
a = ['foo', foo]
b = a.copy()
c = a[:]
d = list(a)
e = copy.copy(a)
f = cop...
What does a lazy val do?
...pendent or cyclic structures. E.g. this leads to an stack overflow:
trait Foo { val foo: Foo }
case class Fee extends Foo { val foo = Faa() }
case class Faa extends Foo { val foo = Fee() }
println(Fee().foo)
//StackOverflowException
But with lazy vals it works fine
trait Foo { val foo: Foo }
ca...
How to escape braces (curly brackets) in a format string in .NET
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For you to output foo {1, 2, 3} you have to do something like:
string t = "1, 2, 3";
string v = String.Format(" foo {{{0}}}", t);
To output a { you use {{ and to output a } you use }}.
or Now, you can also use c# string interpolation like ...
How to delete duplicates on a MySQL table?
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Doesn't seem to work with InnoDB. I ran ALTER TABLE foo ENGINE MyISAM to work around it, changed the engine back after.
– Martin
Jul 17 '13 at 23:06
13
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How to call a parent class function from derived class function?
...uate it by adding the base class's name followed by two colons base_class::foo(...). You should note that unlike Java and C#, C++ does not have a keyword for "the base class" (super or base) since C++ supports multiple inheritance which may lead to ambiguity.
class left {
public:
void foo();
};...
Inserting a string into a list without getting split into characters
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To add to the end of the list:
list.append('foo')
To insert at the beginning:
list.insert(0, 'foo')
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C#泛型(List)中基类和子类 怎么转换？ - 更多技术 - 清泛网 - 专注C/C++及内核技术
...型(List)中基类和子类 怎么转换？List<ChildClass> childList = ...Foo(List<BaseClass> baseList);需求：把子类列表传入函数Foo，Foo支持所有子类列表。方法一：Foo(ch...List<ChildClass> childList = ...
Foo(List<BaseClass> baseList);
需求：把子类列表传入函数...
Kotlin: how to pass a function as parameter to another?
Given function foo :
10 Answers
10
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What use is find_package() if you need to specify CMAKE_MODULE_PATH anyway?
...ocated within your project. Something like this:
CMakeLists.txt
cmake/FindFoo.cmake
cmake/FindBoo.cmake
CMakeLists.txt content:
list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}/cmake")
find_package(Foo REQUIRED) # FOO_INCLUDE_DIR, FOO_LIBRARIES
find_package(Boo REQUIRED) # BOO_INCLUDE_DI...