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How can I determine if a variable is 'undefined' or 'null'?
...enceError and break execution if variable is not defined or referred to at all in the code, using typeof is safer.
– Mani Gandham
Jun 15 '14 at 9:49
59
...
What SOAP client libraries exist for Python, and where is the documentation for them? [closed]
... I'm doing this to get myself acquainted with both technologies. I've installed SOAPlib and I've tried to read their Client documentation, but I don't understand it too well. Is there anything else I can look into which is more suited for being a SOAP Client library for Python?
...
Is it possible to modify variable in python that is in outer, but not global, scope?
...ld a temporary scope. It's like the mutable but a bit prettier.
def outer_fn():
class FnScope:
b = 5
c = 6
def inner_fn():
FnScope.b += 1
FnScope.c += FnScope.b
inner_fn()
inner_fn()
inner_fn()
This yields the following interactive output:
>>> outer...
Why does pattern matching in Scala not work with variables?
...atch {
case `target` => println("It was" + target)
case _ => println("It was something else")
}
}
def mMatch2(s: String) = {
val Target: String = "a"
s match {
case Target => println("It was" + Target)
case _ => println("It was something else"...
PostgreSQL - Rename database
...isconnect from the database to be renamed
\c postgres
-- force disconnect all other clients from the database to be renamed
SELECT pg_terminate_backend( pid )
FROM pg_stat_activity
WHERE pid <> pg_backend_pid( )
AND datname = 'name of database';
-- rename the database (it should now have...
How does the MapReduce sort algorithm work?
... 1 sampled keys that define the key range for each reduce. In particular, all keys such that sample[i − 1] <= key < sample[i] are sent to reduce i. This guarantees that the output of reduce i are all less than the output of reduce i+1."
So their trick is in the way they determine the keys ...
Pandas: drop a level from a multi-level column index?
...
@yoonghm It is there, you are probably just calling it on columns that don't have a multi-index
– matt harrison
Dec 18 '18 at 14:59
1
...
Disabling Minimize & Maximize On WinForm?
....
If you want to ever actually close the form, make a class-wide boolean _close and, in your handler, set e.Cancel to !_close, so that whenever the user clicks the X on the window, it doesn't close, but you can still close it (without just killing it) with close = true; this.Close();
(And just to...
Test whether string is a valid integer
...
Additionally, based on character collation (see this related question/answer) something like d[g-i]{2} could end up not only matching dig but also dish in the collation suggested by that answer (where the sh digraph is considered a s...
Finding duplicate values in a SQL table
...ly group on both of the columns.
Note: the older ANSI standard is to have all non-aggregated columns in the GROUP BY but this has changed with the idea of "functional dependency":
In relational database theory, a functional dependency is a constraint between two sets of attributes in a relation...