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Is there a minlength validation attribute in HTML5?
...answered Apr 24 '12 at 8:24
user123444555621user123444555621
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How do you build a Singleton in Dart?
...sible way:
void main() {
var s1 = Singleton.instance;
s1.somedata = 123;
var s2 = Singleton.instance;
print(s2.somedata); // 123
print(identical(s1, s2)); // true
print(s1 == s2); // true
//var s3 = new Singleton(); //produces a warning re missing default constructor and breaks on ...
Fastest way to count exact number of rows in a very large table?
...nly speculate. Does the db maintenance process find out that there are 42,123,876 rows in table A and then create 42,123,876 empty rows in table B, and then loop through table A and update the rows in table B...? Or is it crazier than that? ;-)
– Tony Andrews
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How do I replace a git submodule with another repo?
...
123
If the location (URL) of the submodule has changed, then you can simply:
Modify your .gitmod...
How to overwrite the previous print to stdout in python?
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123
One way is to use the carriage return ('\r') character to return to the start of the line with...
How to format a java.sql Timestamp for displaying?
...ERMAN);
Timestamp oldfashionedTimestamp = new Timestamp(1_567_890_123_456L);
ZonedDateTime dateTime = oldfashionedTimestamp.toInstant()
.atZone(ZoneId.systemDefault());
String desiredFormat = dateTime.format(formatter);
System.out.println(desiredFormat);
O...
Printing the last column of a line in a file
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Using Perl
$ cat rayne.txt
A1 123 456
B1 234 567
C1 345 678
A1 098 766
B1 987 6545
C1 876 5434
$ perl -lane ' /A1/ and $x=$F[2] ; END { print "$x" } ' rayne.txt
766
$
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Ruby replace string with captured regex pattern
...note that you can index a string with a regex:
"foo"[/oo/]
#=> "oo"
"Z_123: foobar"[/^Z_.*(?=:)/]
#=> "Z_123"
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Creating PHP class instance with a string
...ther cool stuff you can do in php are:
Variable variables:
$personCount = 123;
$varname = 'personCount';
echo $$varname; // echo's 123
And variable functions & methods.
$func = 'my_function';
$func('param1'); // calls my_function('param1');
$method = 'doStuff';
$object = new MyClass();
$obj...
Difference between 2 dates in SQLite
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123
SELECT julianday('now') - julianday(DateCreated) FROM Payment;
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