大约有 23,000 项符合查询结果（耗时：0.0257秒） [XML]
Using unset vs. setting a variable to empty
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var= is not "not set". It's just an unquoted empty string. In addition to set -u, bash's various forms of parameter expansion can also distinguish between unset and null values: ${foo:bar} expands to "bar" when foo is unset, but "" when foo is null, while ${foo:-bar} expands ...
Can I make git recognize a UTF-16 file as text?
... solution that works out of the box on Unices.
For example, with Apple's .strings files just:
Create a .gitattributes file in the root of your repository with:
*.strings diff=localizablestrings
Add the following to your ~/.gitconfig file:
[diff "localizablestrings"]
textconv = "iconv -f utf-16...
How can I check if the current date/time is past a set date/time?
...5-15 16:00:00
# in other words, 2010-05-15 16:00:00 has passed
}
The string passed to the DateTime constructor is parsed according to these rules.
Note that it is also possible to use time and strtotime functions. See original answer.
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How to search for “R” materials? [closed]
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Joining this discussion very late, but here is my preferred search string in Google: [R] followed by search string.
For example:
[R] lm finds several links to linear modelling in R
The reason this works is that StackOverflow uses the [r] tag, and the R mailing lists also use [R].
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.prop() vs .attr()
...lly simpler to deal with than attributes. An attribute value may only be a string whereas a property can be of any type. For example, the checked property is a Boolean, the style property is an object with individual properties for each style, the size property is a number.
Where both a property and...
How do I get the number of days between two dates in JavaScript?
...umber value (milliseconds since the start of 1970).
// new Date("dateString") is browser-dependent and discouraged, so we'll write
// a simple parse function for U.S. date format (which does no error checking)
function parseDate(str) {
var mdy = str.split('/');
return new Date(mdy[...
How to dynamically build a JSON object with Python?
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You build the object before encoding it to a JSON string:
import json
data = {}
data['key'] = 'value'
json_data = json.dumps(data)
JSON is a serialization format, textual data representing a structure. It is not, itself, that structure.
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Why is super.super.method(); not allowed in Java?
... + ((I)this).x);
}
}
class Test {
public static void main(String[] args) {
new T3().test();
}
}
which produces the output:
x= 3
super.x= 2
((T2)this).x= 2
((T1)this).x= 1
((I)this).x= 0
(example from the JLS)
However, this do...
Counting array elements in Python [duplicate]
... the number of elements in an array, because contrary to logic array.count(string) does not count all the elements in the array, it just searches for the number of occurrences of string.
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Where are the PostgreSQL logs on macOS?
...>
<dict>
[...]
<key>StandardErrorPath</key>
<string>/usr/local/var/postgres/server.log</string>
</dict>
</plist>
So in this case, /usr/local/var/postgres/server.log.
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