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What is the maximum length of a valid email address?
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1237
An email address must not exceed 254 characters.
This was accepted by the IETF following submi...
regex to match a single character that is anything but a space
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263
The following should suffice:
[^ ]
If you want to expand that to anything but white-space (li...
How to reshape data from long to wide format
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answered May 4 '11 at 23:20
ChaseChase
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How to “crop” a rectangular image into a square with CSS?
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answered Mar 1 '13 at 22:04
MichaelMichael
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for each loop in Objective-C for accessing NSMutable dictionary
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edited May 24 '18 at 7:37
Iulian Onofrei
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answ...
Extracting the last n characters from a string in R
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edited Nov 1 '11 at 12:30
answered Nov 1 '11 at 8:19
And...
How to increase font size in a plot in R?
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Dirk EddelbuettelDirk Eddelbuettel
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How to do what head, tail, more, less, sed do in Powershell? [closed]
...elect -last 10 # tail
gc -Tail 10 log.txt # also tail (since PSv3), also much faster than above option
gc log.txt | more # or less if you have it installed
gc log.txt | %{ $_ -replace '\d+', '($0)' } # sed
This works well enough for small files, larger ones (more tha...
Is there a difference between “==” and “is”?
...e objects referred to by the variables are equal.
>>> a = [1, 2, 3]
>>> b = a
>>> b is a
True
>>> b == a
True
# Make a new copy of list `a` via the slice operator,
# and assign it to variable `b`
>>> b = a[:]
>>> b is a
False
>>> b ...
Creating PHP class instance with a string
...er 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();
$objec...