大约有 4,600 项符合查询结果（耗时：0.0389秒） [XML]
Why it's not possible to use regex to parse HTML/XML: a formal explanation in layman's terms
... or bonbon. Matching of recursive/balanced structures make these even more fun.
Wikipedia puts this nicely, in a quote by Larry Wall:
'Regular expressions' [...] are only marginally related to real regular expressions. Nevertheless, the term has grown with the capabilities of our pattern matchi...
How does Google's Page Speed lossless image compression work?
... answered Dec 5 '12 at 6:19
user123444555621user123444555621
123k2323 gold badges101101 silver badges120120 bronze badges
...
How to make Sequelize use singular table names
...freezeTableName: true
}
}
var sequelize = new Sequelize('mysql://root:123abc@localhost:3306/mydatabase', opts)
Now when you define your entities, you don't have to specify freezeTableName: true:
var Project = sequelize.define('Project', {
title: Sequelize.STRING,
description: Sequeli...
How to sort in-place using the merge sort algorithm?
...he rest as working area for merging.
For example like the following merge function.
void wmerge(Key* xs, int i, int m, int j, int n, int w) {
while (i < m && j < n)
swap(xs, w++, xs[i] < xs[j] ? i++ : j++);
while (i < m)
swap(xs, w++, i++);
while (...
Adding new column to existing DataFrame in Python pandas
...)
As per this example (which also includes the source code of the assign function), you can also include more than one column:
df = pd.DataFrame({'a': [1, 2], 'b': [3, 4]})
>>> df.assign(mean_a=df.a.mean(), mean_b=df.b.mean())
a b mean_a mean_b
0 1 3 1.5 3.5
1 2 4 1...
Null vs. False vs. 0 in PHP
...ill get inequality.
So why are they useful ?
Well, look at the strrpos() function. It returns False if it did not found anything, but 0 if it has found something at the beginning of the string !
<?php
// pitfall :
if (strrpos("Hello World", "Hello")) {
// never exectuted
}
// smart move ...
Purpose of asterisk before a CSS property
...dited Sep 4 '14 at 21:33
hichris123
9,5151212 gold badges5050 silver badges6666 bronze badges
answered Nov 6 '09 at 21:44
...
Insert, on duplicate update in PostgreSQL?
...RT, as appropriate:
CREATE TABLE db (a INT PRIMARY KEY, b TEXT);
CREATE FUNCTION merge_db(key INT, data TEXT) RETURNS VOID AS
$$
BEGIN
LOOP
-- first try to update the key
-- note that "a" must be unique
UPDATE db SET b = data WHERE a = key;
IF found THEN
...
how to “reimport” module to python then code be changed after import
... edited Mar 9 '17 at 5:41
Seanny123
5,70277 gold badges4949 silver badges100100 bronze badges
answered Oct 23 '16 at 15:41
...
Why do we need message brokers like RabbitMQ over a database like PostgreSQL?
...em) on top of a database. I can tell you that it is possible, but it's not fun and it doesn't usually pay off to do it. Some of the problems you mention can be worked around, but it does increase the complexity quite a lot. All in all I agree: use a dedicated MQ system, if you need one. For low work...