大约有 44,000 项符合查询结果(耗时:0.0444秒) [XML]
Get the first element of each tuple in a list in Python [duplicate]
...
Use a list comprehension:
res_list = [x[0] for x in rows]
Below is a demonstration:
>>> rows = [(1, 2), (3, 4), (5, 6)]
>>> [x[0] for x in rows]
[1, 3, 5]
>>>
Alternately, you could use unpacking instead of x[0]:
res_li...
手机蓝牙控制台灯:HC-05 开关、无级调光、定时关灯(附 .aia 源码与单片机...
...给 Connect,组件会自己截取前面的地址。
when 列表选择器_设备.BeforePicking() {
列表选择器_设备.Elements = 蓝牙客户端1.AddressesAndNames
}
when 列表选择器_设备.AfterPicking() {
if 蓝牙客户端1.Connect(列表选择器_设备.Selection) {
微数据...
What is the type of lambda when deduced with “auto” in C++11?
... is no such thing as "a name the compiler decides upon". The result of type_info::name() is implementation-defined, so it may return anything. In practice, the compiler will name the type for the sake of the linker.
– avakar
Oct 31 '11 at 19:46
...
Using mixins vs components for code reuse in Facebook React
...nding fields.
Source (gist)
define(function () {
'use strict';
var _ = require('underscore');
var ValidationMixin = {
getInitialState: function () {
return {
errors: []
};
},
componentWillMount: function () {
this.assertValidatorsDefined();
},
...
JavaScript function similar to Python range()
...to xrange in Python2:
function range(low, high) {
return {
__iterator__: function() {
return {
next: function() {
if (low > high)
throw StopIteration;
return low++;
}
...
Most efficient way to remove special characters from string
...ed characters are A-Z (uppercase or lowercase), numbers (0-9), underscore (_), or the dot sign (.).
24 Answers
...
ElasticSearch: Unassigned Shards, how to fix?
...enable shard allocation.
# v0.90.x and earlier
curl -XPUT 'localhost:9200/_settings' -d '{
"index.routing.allocation.disable_allocation": false
}'
# v1.0+
curl -XPUT 'localhost:9200/_cluster/settings' -d '{
"transient" : {
"cluster.routing.allocation.enable" : "all"
}
}'
Elas...
What is the best way to ensure only one instance of a Bash script is running? [duplicate]
...e
### HEADER ###
LOCKFILE="/var/lock/`basename $0`"
LOCKFD=99
# PRIVATE
_lock() { flock -$1 $LOCKFD; }
_no_more_locking() { _lock u; _lock xn && rm -f $LOCKFILE; }
_prepare_locking() { eval "exec $LOCKFD>\"$LOCKFILE\""; trap _no_more_locking EXIT; }
# ON START
_prepare_l...
搭建高可用mongodb集群(一)——配置mongodb - 大数据 & AI - 清泛网 - 专...
...安装程序包
wget http://fastdl.mongodb.org/linux/mongodb-linux-x86_64-2.4.6.tgz
#解压下载的压缩包
tar xvzf mongodb-linux-x86_64-2.4.6.tgz
#进入mongodb程序执行文件夹
cd mongodb-linux-x86_64-2.4.6/bin/
3、启动单实例mongodb
mongod --dbpath /data/mongodbtest/...
class
...odule ("static") methods:
class String
class << self
def value_of obj
obj.to_s
end
end
end
String.value_of 42 # => "42"
This can also be written as a shorthand:
class String
def self.value_of obj
obj.to_s
end
end
Or even shorter:
def String.value_of obj
...
