大约有 31,500 项符合查询结果（耗时：0.0358秒） [XML]
if A vs if A is not None:
...
The statement
if A:
will call A.__nonzero__() (see Special method names documentation) and use the return value of that function. Here's the summary:
object.__nonzero__(self)
Called to implement truth value testing and the built-in operation ...
Struct constructor: “fields must be fully assigned before control is returned to the caller.”
...
@RogerWillcocks, just call the default constructor then: public YourStruct(some params) : this() (see vittore's answer)
– Thomas Levesque
Nov 27 '12 at 2:25
...
It is more efficient to use if-return-return or if-else-return?
...the if condition is false anyway.
Note that Python supports a syntax that allows you to use only one return statement in your case:
return A+1 if A > B else A-1
share
|
improve this answer
...
Get all git commits since last tag
...
If your current commit is also a tag and you want to dynamically get the changes since the previous tag, without knowing the latest tag nor previous tag name, you can do:
git log --oneline $(git describe --tags --abbrev=0 @^)..@
Note that @ is short for HEAD.
...
subtle differences between JavaScript and Lua [closed]
...= operators are of lower precedence than >, >=, <, <=. In Lua, all comparison operators are the same precedence.
Lua supports tail calls.
UPDATE: JS now supports tail calls.
Lua supports assignment to a list of variables. While it isn't yet standard in Javascript, Mozilla's JS engine ...
What are the benefits of Java's types erasure?
...about type erasure, which is the only thing Java got right, while ignoring all the things it got wrong.
I get huge benefits (e.g. parametricity) and nil cost (alleged cost is a limit of imagination).
new T is a broken program. It is isomorphic to the claim "all propositions are true." I am not big ...
Algorithms based on number base systems? [closed]
...ctional Data Structures that discusses "Numerical Representations": essentially, take some representation of a number and convert it into a data structure. To give a flavor, here are the sections of that chapter:
Positional Number Systems
Binary Numbers (Binary Random-Access Lists, Zeroless Repres...
How to preventDefault on anchor tags?
...fault();
});
}
}
};
});
It checks all anchor tags (<a></a>) to see if their href attribute is either an empty string ("") or a hash ('#') or there is an ng-click assignment. If it finds any of these conditions, it catches the event and prevents t...
Code block in numbered list (Wiki syntax)
...two
It is not perfect, because you end up with a more indent but it does allow one to use the wiki syntax for correctly formatted pre blocks over multiple lines.
As previously mentioned, the other proper way would be to use HTML mark up.
<ol>
<li>one</li>
<li>two</li&g...
MassAssignmentException in Laravel
...ection against mass assignment security issues. That's why you have to manually define which fields could be "mass assigned" :
class User extends Model
{
protected $fillable = ['username', 'email', 'password'];
}
Warning : be careful when you allow the mass assignment of critical fields lik...