大约有 45,000 项符合查询结果（耗时：0.0558秒） [XML]
Extract substring using regexp in plain bash
I'm trying to extract the time from a string using bash, and I'm having a hard time figuring it out.
4 Answers
...
Convert HH:MM:SS string to seconds only in javascript
...perator to convert numeric string to number is not a good idea. It's short and looks "clever", but it's confusing and not clean code. Use parseInt(x, 10) instead. And avoid one-liner. Also prevent errors by undefined input. For example: it's not a string, has no ":" or only "HH:MM". etc.
...
Should I use string.isEmpty() or “”.equals(string)?
...equals(s) is you don't need the null check (equals will check its argument and return false if it's null), which you seem to not care about. If you're not worried about s being null (or are otherwise checking for it), I would definitely use s.isEmpty(); it shows exactly what you're checking, you ca...
List all indexes on ElasticSearch server?
...curl http://localhost:9200/_aliases
this will give you a list of indices and their aliases.
If you want it pretty-printed, add pretty=true:
curl http://localhost:9200/_aliases?pretty=true
The result will look something like this, if your indices are called old_deuteronomy and mungojerrie:
{
...
Are tuples more efficient than lists in Python?
Is there any performance difference between tuples and lists when it comes to instantiation and retrieval of elements?
8 A...
Value of i for (i == -i && i != 0) to return true in Java
...000000000000000000
Taking the negative value is done by first swapping 0 and 1, which gives
01111111111111111111111111111111
and by adding 1, which gives
10000000000000000000000000000000
As you can see in the link I gave, Wikipedia mentions the problem with the most negative numbers and spec...
What's a concise way to check that environment variables are set in a Unix shell script?
...(an empty string) is OK — not exactly what you want, but the alternative and older notation.
The second variant (using :?) requires DEST to be set and non-empty.
If you supply no message, the shell provides a default message.
The ${var?} construct is portable back to Version 7 UNIX and the Bourne ...
best way to preserve numpy arrays on disk
...
h5py example and pytables example
– Kamil Slowikowski
Sep 23 '16 at 13:15
...
Can I set max_retries for requests.request?
The Python requests module is simple and elegant but one thing bugs me.
It is possible to get a requests.exception.ConnectionError with a message like:
...
Regular expression to match a word or its prefix
...
Square brackets are meant for character class, and you're actually trying to match any one of: s, |, s (again), e, a, s (again), o and n.
Use parentheses instead for grouping:
(s|season)
or non-capturing group:
(?:s|season)
Note: Non-capture groups tell the engin...