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What is a regular expression which will match a valid domain name without a subdomain?
...specs, your specs are wrong. g.co is a valid domain name but g is only one character.
– sch
Apr 24 '12 at 22:23
3
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How to declare an array in Python?
... contains references to items. Also, underlying array is created with some extra space.
Consequences of this are:
random access is really cheap (arr[6653] is same to arr[0])
append operation is 'for free' while some extra space
insert operation is expensive
Check this awesome table of operation...
Overloading Macro on Number of Arguments
... expand the _COUNT_ARGS(__VA_ARGS__) part, which otherwise is treated as a string.
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What is the difference between . (dot) and $ (dollar sign)?
...fore cannot be used with the . operator.
show can take an Int and return a String.
putStrLn can take a String and return an IO ().
You can chain show to putStrLn like this:
(putStrLn . show) (1 + 1)
If that's too many parentheses for your liking, get rid of them with the $ operator:
putStrLn ....
How to handle configuration in Go [closed]
...ing/json"
"os"
"fmt"
)
type Configuration struct {
Users []string
Groups []string
}
file, _ := os.Open("conf.json")
defer file.Close()
decoder := json.NewDecoder(file)
configuration := Configuration{}
err := decoder.Decode(&configuration)
if err != nil {
fmt.Println("err...
Reading a file line by line in Go
...tion into your own function which calls ReadLine in a for-loop.
bufio.ReadString('\n') isn't fully equivalent to ReadLine because ReadString is unable to handle the case when the last line of a file does not end with the newline character.
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How to append a newline to StringBuilder
I have a StringBuilder object,
9 Answers
9
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What does $_ mean in PowerShell?
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Working version with extra pipeline removed. gci | % { add-member -InputObject $_ -Type NoteProperty -Name Bar -Value $_.name -PassThru } | Select Bar
– Xalorous
Nov 23 '15 at 19:27
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Concatenate multiple result rows of one column into one, group by another column [duplicate]
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Simpler with the aggregate function string_agg() (Postgres 9.0 or later):
SELECT movie, string_agg(actor, ', ') AS actor_list
FROM tbl
GROUP BY 1;
The 1 in GROUP BY 1 is a positional reference and a shortcut for GROUP BY movie in this case.
string_agg() ...
how to delete all cookies of my website in php
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There's no difference so far as I can tell (except the extra work).
– jasonbar
Feb 22 '10 at 12:35
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