大约有 30,000 项符合查询结果（耗时：0.0416秒） [XML]
Why do we usually use || over |? What is the difference?
...onsider the following example.
Boolean b = true;
if(b || foo.timeConsumingCall())
{
//we entered without calling timeConsumingCall()
}
Another benefit, as Jeremy and Peter mentioned, for short-circuiting is the null reference check:
if(string != null && string.isEmpty())
{
//we c...
List passed by ref - help me explain this behaviour
...list, but your aren't passing the list variable by reference - so when you call ChangeList the value of the variable (i.e. the reference - think "pointer") is copied - and changes to the value of the parameter inside ChangeList aren't seen by TestMethod.
try:
private void ChangeList(ref List<in...
Java 32-bit vs 64-bit compatibility
...VM rather than a 32bit VM and didn't notice until some external libraries (called by JNI) started failing.
Data serialized on a 32bit platform was read in on the 64bit platform with no issues at all.
What sort of issues are you getting? Do some things work and not others? Have you tried attaching ...
Deep copying an NSArray
...deeply copy an entire nested data structure — what the linked Apple docs call a true deep copy — then this approach will not suffice. Please see the other answers here for that.
share
|
improve ...
Avoid synchronized(this) in Java?
...ic void blah() {
synchronized (this) {
// do stuff
}
}
is semantically equivalent to:
public synchronized void blah() {
// do stuff
}
which is one reason not to use synchronized(this). You might argue that you can do stuff around the synchronized(this) block. The usual reason is to ...
Filter dict to contain only certain keys?
... is O(n), but depends on hash collision likelihood. You'd need an astronomically large dictionary, or a really crude hashing algorithm to start seeing that be an issue. stackoverflow.com/a/1963514/1335793
– Davos
Oct 5 '17 at 12:57
...
What does tree-ish mean in Git?
...
The Short Answer (TL;DR)
"Tree-ish" is a term that refers to any identifier (as specified in the Git
revisions documentation) that ultimately leads to a (sub)directory
tree (Git refers to directories as "trees" and "tree objects").
In the original poster's case, foo is a directory that he...
How to get POSTed JSON in Flask?
...lalala"})
if res.ok:
print res.json()
The "json=" input will automatically set the content-type, as discussed here: Post JSON using Python Requests
And the above client will work with this server-side code:
from flask import Flask, request, jsonify
app = Flask(__name__)
@app.route('/api/ad...
Is it better in C++ to pass by value or pass by constant reference?
... figure out when passing by value is expensive, and implicitly convert the call to use a const ref if possible.
In theory. In practice, compilers can’t always change this without breaking the function’s binary interface. In some special cases (when the function is inlined) the copy will actuall...
C++ lambda with captures as a function pointer
...cit conversion to function pointers. My starting example was using them as callback for the ftw function. This works as expected.
...