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JavaScript, elegant way to check nested object properties for null/undefined [duplicate]
...tatement would look like if it's undefined), that may be what you want.
example:
try {
user.loc.lat.doSomething();
} catch(error) {
//report
}
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How are booleans formatted in Strings in Python?
...
>>> print "%r, %r" % (True, False)
True, False
This is not specific to boolean values - %r calls the __repr__ method on the argument. %s (for str) should also work.
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Should I use an exception specifier in C++?
...n may or may not throw an exception by using an exception specifier. For example:
14 Answers
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Get local IP address in node.js
...etwork interface names to its properties (so that one interface can, for example, have several addresses):
'use strict';
const { networkInterfaces } = require('os');
const nets = networkInterfaces();
const results = Object.create(null); // or just '{}', an empty object
for (const name of Object.k...
UnmodifiableMap (Java Collections) vs ImmutableMap (Google) [duplicate]
...// Will return "F".
In contrast to that, the ImmutableMap of Guava is really immutable: It is a true copy of a given map, and nobody may modify this ImmutableMap in any way.
Update:
As pointed out in a comment, an immutable map can also be created with the standard API using
Map<String, S...
Oracle 11.2.0.4 RAC FOR redhat 6.4 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
...缓存的情况下可能会报目录不存在的错误,无视
yum clean all
yum makecache
4、安装vncserver,xterm并配置
yum -y install xterm*
yum install -y tigervnc-server
chkconfig --level 345 vncserver on
配置vnc密码
Vncserver
配置为使用gnome桌面
修改 /ro...
Why is the asterisk before the variable name, rather than after the type?
... This point can be misleading in such context: int x = 5; int *pointer = &x;, because it suggests we set the int *pointer to some value, not the pointer itself.
– rafalcieslak
Feb 23 '13 at 20:04
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What is “entropy and information gain”?
...: female
| | ends-vowel=0: male
length>=7
| length=5: male
basically each node represent a test performed on a single attribute, and we go left or right depending on the result of the test. We keep traversing the tree until we reach a leaf node which contains the class prediction (m or f)...
Python __str__ and lists
In Java, if I call List.toString(), it will automatically call the toString() method on each object inside the List. For example, if my list contains objects o1, o2, and o3, list.toString() would look something like this:
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Delete all documents from index/type without deleting type
...l it should do what you are looking for, something like this (using your example):
curl -XDELETE 'http://localhost:9200/twitter/tweet/_query' -d '{
"query" : {
"match_all" : {}
}
}'
Or you could just delete the type:
curl -XDELETE http://localhost:9200/twitter/tweet
...
