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Scala: What is a TypeTag and how do I use it?
...ss Foo
class Bar extends Foo
def meth[A](xs: List[A]) = xs match {
case _: List[String] => "list of strings"
case _: List[Foo] => "list of foos"
}
we will get warnings:
<console>:23: warning: non-variable type argument String in type pattern List[String]↩
is unchecked since it ...
Reference: What is variable scope, which variables are accessible from where and what are “undefined
...
@Arthur There is so much to unpack there… ಠ_ಠ This is most certainly not an approach I would endorse.
– deceze♦
Aug 3 '17 at 8:24
...
Equals(=) vs. LIKE
...the = comparison operator:
mysql> SELECT 'ä' LIKE 'ae' COLLATE latin1_german2_ci;
+-----------------------------------------+
| 'ä' LIKE 'ae' COLLATE latin1_german2_ci |
+-----------------------------------------+
| 0 |
+----------------------------------...
How to copy a row and insert in same table with a autoincrement field in MySQL?
...
Use INSERT ... SELECT:
insert into your_table (c1, c2, ...)
select c1, c2, ...
from your_table
where id = 1
where c1, c2, ... are all the columns except id. If you want to explicitly insert with an id of 2 then include that in your INSERT column list and your SE...
ZSH complains about RVM __rvm_cleanse_variables: function definition file not found
...
searched for "whats 'zcompdump' for" while diagnosing the __rvm_cleanse_variables issue... two birds, one search. +1's to everyone.
– max
Mar 21 '15 at 18:54
...
How do you round to 1 decimal place in Javascript?
...)
You might want to create a function for this:
function roundedToFixed(_float, _digits){
var rounded = Math.pow(10, _digits);
return (Math.round(_float * rounded) / rounded).toFixed(_digits);
}
share
|
...
How to toggle a value in Python
...; toggle()
'blue'
Note that in Python 3 the next() method was changed to __next__(), so the first line would be now written as toggle = itertools.cycle(['red', 'green', 'blue']).__next__
share
|
i...
mysql_fetch_array()/mysql_fetch_assoc()/mysql_fetch_row()/mysql_num_rows etc… expects parameter 1 to
...
A query may fail for various reasons in which case both the mysql_* and the mysqli extension will return false from their respective query functions/methods. You need to test for that error condition and handle it accordingly.
mysql_* extension:
NOTE The mysql_ functions are deprecate...
What is the maximum recursion depth in Python, and how to increase it?
...mple context manager like this:
import sys
class recursionlimit:
def __init__(self, limit):
self.limit = limit
self.old_limit = sys.getrecursionlimit()
def __enter__(self):
sys.setrecursionlimit(self.limit)
def __exit__(self, type, value, tb):
sys.setr...
Response.Redirect to new window
...owing to your server side link/button:
OnClientClick="aspnetForm.target ='_blank';"
My entire button code looks something like:
<asp:LinkButton ID="myButton" runat="server" Text="Click Me!"
OnClick="myButton_Click"
OnClientClick="aspnetForm.target ='_blank';"...