大约有 47,000 项符合查询结果（耗时：0.0620秒） [XML]
Why hasn't functional programming taken over yet?
... programming (languages), tried out Haskell as well as written one myself. From what I've seen, functional programming has several advantages over the classical imperative style:
...
Collections.emptyMap() vs new HashMap()
...
From Effective Java, Item #43 - "Return empty arrays or collections, not null" demonstrates returning an empty collection and perhaps even demonstrates using these emptyList(), emptySet(), and emptyMap() methods on the Colle...
Express: How to pass app-instance to routes from a different file?
...) method!
documentation - http://expressjs.com/4x/api.html#router
Example from their new generator:
Writing the route: https://github.com/expressjs/generator/blob/master/templates/js/routes/index.js
Adding/namespacing it to the app:
https://github.com/expressjs/generator/blob/master/templates/js/ap...
Array versus List: When to use which?
...tually no collections are ever mutated. That is; collections are retrieved from the database or constructed from some source, but further processing is always done by recreating a new collection (e.g. map/filter etc). Even where conceptual mutation is necessary, it tends to be simplest to just gener...
_DEBUG vs NDEBUG
...
NDEBUG isn't defined when using applications templates from Windows Driver Kit 8.1 too. In this case, you may need to rely on _DEBUG.
– navossoc
Apr 7 '16 at 15:36
...
Check if one list contains element from the other
...the
specified collection (optional operation). In other words, removes
from this list all of its elements that are not contained in the
specified collection.
true if this list changed as a result of the call
Its like
boolean b = list1.retainAll(list2);
...
Why do loggers recommend using a logger per class?
...resort to more reflection tricks to know where the log messages are coming from.
Compare the following:
Log per class
using System.Reflection;
private static readonly ILog _logger =
LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
public void SomeMethod()
{
_logge...
Why there is no ConcurrentHashSet against ConcurrentHashMap
...no built in type for ConcurrentHashSet because you can always derive a set from a map. Since there are many types of maps, you use a method to produce a set from a given map (or map class).
Prior to Java 8, you produce a concurrent hash set backed by a concurrent hash map, by using Collections.newS...
How to merge dictionaries of dictionaries?
... makes the "reduce" easier to explain]
ps in python 3, you will also need from functools import reduce
share
|
improve this answer
|
follow
|
...
pythonic way to do something N times without an index variable?
...ul -- except for the fact that you're used to it, why else would "count up from 0 to N-1 [[and completely ignore the count]] each time performing this count-independent operation" be intrinsically any clearer than "repeat N times the following operation"...?
– Alex Martelli
...