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html select option separator
...on>First</option>
</optgroup>
<optgroup label="_________">
<option>Second</option>
<option>Third</option>
</optgroup>
</select>
disabled option (a bit better):
<select>
<option>Fir...
Can I call memcpy() and memmove() with “number of bytes” set to zero?
... the length of the array for a
function, n can have the value zero on a call to that function. Unless explicitly stated
otherwise in the description of a particular function in this subclause, pointer arguments
on such a call shall still have valid values, as described in 7.1.4. On such a call...
How to convert list of tuples to multiple lists?
...
xs, ys = [x for x, y in zs], [y for x, y in zs]
return xs, ys
if __name__ == '__main__':
from timeit import timeit
setup_string='''\
N = 2000000
xs = list(range(1, N))
ys = list(range(N+1, N*2))
zs = list(zip(xs, ys))
from __main__ import t1, t2, t3
'''
print(f'zip:\t\t{timeit(...
Rails: confused about syntax for passing locals to partials
...:partial => 'foo', :locals => {blah blah blah}) then it will pass in all of your arguments as a hash and parse them accordingly.
If you pass in a string as your first argument, it assumes the first argument is your partial name, and will pass the remainder as your locals. However, in that s...
How do I add options to a DropDownList using jQuery?
...orting it.
What we can do is, create a new select element and then append all options. Once loop is finished, append it to actual DOM object.
var myOptions = {
val1 : 'text1',
val2 : 'text2'
};
var _select = $('<select>');
$.each(myOptions, function(val, text) {
_select.append(
...
How To Change DataType of a DataColumn in a DataTable?
... of the column after the DataTable is filled, you can change it after you call FillSchema, but before you call Fill. For example, say the 3rd column is the one you want to convert from double to Int32, you could use:
adapter.FillSchema(table, SchemaType.Source);
table.Columns[2].DataType = typeof (...
How do I calculate tables size in Oracle
Being used to (and potentially spoiled by) MSSQL, I'm wondering how I can get at tables size in Oracle 10g.
I have googled it so I'm now aware that I may not have as easy an option as sp_spaceused. Still the potential answers I got are most of the time outdated or don't work. Probably because I'm no...
Difference between assertEquals and assertSame in phpunit?
...
I use both sporadically, but according to the docs:
assertSame
Reports an error identified by $message if the two variables $expected and $actual do not have the same type and value."
And as you can see in the example below the above exc...
Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
...ull
IL_0002: stloc.0 // s
IL_0003: ldloc.0 // s
IL_0004: callvirt System.String.get_Length
IL_0009: call System.Console.WriteLine
It is the callvirt opcode that throws the NullReferenceException and it does that when the first argument on the evaluation stack is a null ...
How to base64 encode image in linux bash / shell
...
You need to use cat to get the contents of the file named 'DSC_0251.JPG', rather than the filename itself.
test="$(cat DSC_0251.JPG | base64)"
However, base64 can read from the file itself:
test=$( base64 DSC_0251.JPG )
...