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std::function and std::bind: what are they, and when should they be used?
I know what functors are and when to use them with std algorithms, but I haven't understood what Stroustrup says about them in the C++11 FAQ .
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Why am I getting a “401 Unauthorized” error in Maven?
...f you supply the wrong credentials (password etc). You also get an error (and off the top of my head is also a 401) if you try to publish something to a releases repository and that version already exists in the repository. So you might find that by publishing from the command line it works, but t...
Extract a substring according to a pattern
...we create a data frame with two columns, one for the part before the colon and one for after, and then extract the latter.
library(dplyr)
library(tidyr)
library(purrr)
DF <- data.frame(string)
DF %>%
separate(string, into = c("pre", "post")) %>%
pull("post")
## [1] "E001" "E002" "E00...
Bash conditionals: how to “and” expressions? (if [ ! -z $VAR && -e $VAR ])
I guess I'm not clear on how to do "and" tests. I wanted to make sure an argument existed which was working well with [ -e $VAR ] , but it turns out that was also evaluating as true on an empty string; which I do not want.
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When should one use final for method parameters and local variables?
... references ( for example ) that suggest using final as much as possible and I'm wondering how important that is. This is mainly in the the context of method parameters and local variables, not final methods or classes. For constants, it makes obvious sense.
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How to secure MongoDB with username and password
... for the user name & password. I tried the tutorial from the MongoDB site and did following:
15 Answers
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Bash script to calculate time elapsed
...a script in bash to calculate the time elapsed for the execution of my commands, consider:
10 Answers
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Does Python have an ordered set?
...s referred to from the Python 2 Documentation. This runs on Py2.6 or later and 3.0 or later without any modifications. The interface is almost exactly the same as a normal set, except that initialisation should be done with a list.
OrderedSet([1, 2, 3])
This is a MutableSet, so the signature for ...
Why exactly is eval evil?
I know that Lisp and Scheme programmers usually say that eval should be avoided unless strictly necessary. I’ve seen the same recommendation for several programming languages, but I’ve not yet seen a list of clear arguments against the use of eval . Where can I find an account of the potentia...
Changing Java Date one hour back
...ary of the fact that there is Calendar.HOUR which works with 12 hour clock and Calendar.HOUR_OF_DAY for 24 hour clock: chintat.blogspot.ca/2006/05/…
– Wolf
Apr 27 '15 at 17:24
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