大约有 48,000 项符合查询结果（耗时：0.0624秒） [XML]
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...
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.
...
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...
How do I get the path and name of the file that is currently executing?
...vide an example? I've answered similar question using inspect.getabsfile() and it worked for all cases that I've tried.
– jfs
Apr 5 '14 at 17:04
4
...
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...
What is the difference between Trap and Interrupt?
What is the difference between Trap and Interrupt?
9 Answers
9
...
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
...
Bash script to calculate time elapsed
...a script in bash to calculate the time elapsed for the execution of my commands, consider:
10 Answers
...
The forked VM terminated without saying properly goodbye. VM crash or System.exit called
Please help me to solve this issue. I do not exactly understand what the error in the log means.
48 Answers
...
What is a monad?
...t necessarily “good”. They are a pattern which is sometimes beneficial and sometimes not.
Do note that the monadic patten can be combined in a different way:
[1,2,3].flatMap(a => [a + 1].flatMap(b => b != 3 ? [b] : []))
Here the binding is nested rater than chained, but the result is the ...