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How to len(generator()) [duplicate]
...after all.
Generators are functions with a internal state (and fancy syntax). You can repeatedly call them to get a sequence of values, so you can use them in loop. But they don't contain any elements, so asking for the length of a generator is like asking for the length of a function.
if func...
How to check if a table exists in a given schema
...
It depends on what you want to test exactly.
Information schema?
To find "whether the table exists" (no matter who's asking), querying the information schema (information_schema.tables) is incorrect, strictly speaking, because (per documentation):
Only tho...
Can I invoke an instance method on a Ruby module without including it?
...esn't mean that I want to pollute my namespace with all of them. A simple example if there's a Files.truncate and a Strings.truncate and I want to use both in the same class, explicitly. Creating a new class/instance each time I need a specific method or modifying the original is not a nice approach...
LINQ to SQL Left Outer Join
...0-1. To do a left outer join, you need SelectMany and DefaultIfEmpty, for example:
var query = from c in db.Customers
join o in db.Orders
on c.CustomerID equals o.CustomerID into sr
from x in sr.DefaultIfEmpty()
select new {
CustomerI...
Where are Docker images stored on the host machine?
...has some running containers with images, will it migrate the date on the next restart of the daemon? If not then how to modify the storage driver in this case?
– BTR Naidu
Apr 12 '16 at 13:54
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How to put individual tags for a scatter plot
...ot in matplotlib and I couldn't find a way to add tags to the points. For example:
1 Answer
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What does void* mean and how to use it?
...ter type. A void * can be converted to any other pointer type without an explicit cast. You cannot dereference a void * or do pointer arithmetic with it; you must convert it to a pointer to a complete data type first.
void * is often used in places where you need to be able to work with different...
How to upgrade Git to latest version on macOS?
I just bought a new Mac with OS X Lion and I checked in the Terminal what version of git is installed by default. I got the answer
...
How to permanently remove few commits from remote branch
...reset --hard your local branch to remove changes from working tree and index, and you git push --force your revised local branch to the remote. (other solution here, involving deleting the remote branch, and re-pushing it)
This SO answer illustrates the danger of such a command, especially if peopl...
Select arrow style change
...ing like this:
.styled-select select {
-moz-appearance:none; /* Firefox */
-webkit-appearance:none; /* Safari and Chrome */
appearance:none;
}
Haven't tested, but should work.
EDIT: It looks like Firefox doesn't support this feature up until version 35 (read more here)
There is a wo...