大约有 40,000 项符合查询结果（耗时：0.0382秒） [XML]
Iterate over the lines of a string
...< 0: break
yield foo[prevnl + 1:nextnl]
prevnl = nextnl
if __name__ == '__main__':
for f in f1, f2, f3:
print list(f())
Running this as the main script confirms the three functions are equivalent. With timeit (and a * 100 for foo to get substantial strings for more precise me...
How to copy a row and insert in same table with a autoincrement field in MySQL?
...
Use INSERT ... SELECT:
insert into your_table (c1, c2, ...)
select c1, c2, ...
from your_table
where id = 1
where c1, c2, ... are all the columns except id. If you want to explicitly insert with an id of 2 then include that in your INSERT column list and your SE...
How to properly reuse connection to Mongodb across NodeJs application and modules
...re( 'mongodb' ).MongoClient;
const url = "mongodb://localhost:27017";
var _db;
module.exports = {
connectToServer: function( callback ) {
MongoClient.connect( url, { useNewUrlParser: true }, function( err, client ) {
_db = client.db('test_db');
return callback( err );
} );...
How to get object length [duplicate]
...ize method, as well as a toArray method, which may get you what you need.
_.size({one : 1, two : 2, three : 3});
=> 3
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Remove duplicate entries using a Bash script [duplicate]
...
Perl one-liner similar to @kev's awk solution:
perl -ne 'print if ! $a{$_}++' input
This variation removes trailing whitespace before comparing:
perl -lne 's/\s*$//; print if ! $a{$_}++' input
This variation edits the file in-place:
perl -i -ne 'print if ! $a{$_}++' input
This variation e...
How to force ASP.NET Web API to always return JSON?
...otiator : IContentNegotiator
{
private readonly JsonMediaTypeFormatter _jsonFormatter;
public JsonContentNegotiator(JsonMediaTypeFormatter formatter)
{
_jsonFormatter = formatter;
}
public ContentNegotiationResult Negotiate(
Type type,
Http...
How to create a date object from string in javascript [duplicate]
...return a JS Date object, with a robust selection of methods available from __proto__. Demo in jsFiddle
– KyleMit
Apr 11 '17 at 19:19
4
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Curly braces in string in PHP
...eral {$. Some examples to make it clear:
<?php
// Show all errors
error_reporting(E_ALL);
$great = 'fantastic';
// Won't work, outputs: This is { fantastic}
echo "This is { $great}";
// Works, outputs: This is fantastic
echo "This is {$great}";
echo "This is ${great}";
// Works
echo "This sq...
remove objects from array by object property
...d:'efg',name:'em'},
{id:'hij',name:'ge'}];
items.splice(_.indexOf(items, _.findWhere(items, { id : "abc"})), 1);
With ES5 or higher
(without lodash/underscore)
With ES5 onwards we have findIndex method on array, so its easy without lodash/underscore
items.splice(items.findIn...
Programmatically find the number of cores on a machine
...<thread>
//may return 0 when not able to detect
const auto processor_count = std::thread::hardware_concurrency();
Reference: std::thread::hardware_concurrency
In C++ prior to C++11, there's no portable way. Instead, you'll need to use one or more of the following methods (guarded by app...