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Finding the number of days between two dates
...t all of Europe moved the clock back an hour. That means that today has an extra 3600 seconds, and that ought to be reflected in the UNIX timestamps. If it is, then that means that today will count for two days with the above way of computing the number of days. And I'm not even starting about leap ...
How to remove from a map while iterating it?
...r this pattern which is slightly clearer and simpler, at the expense of an extra variable:
for (auto it = m.cbegin(), next_it = it; it != m.cend(); it = next_it)
{
++next_it;
if (must_delete)
{
m.erase(it);
}
}
Advantages of this approach:
the for loop incrementor makes sense as an ...
What is Weak Head Normal Form?
...thunks. In this case, t1 would be your 0 (or rather, a thunk to 0 given no extra unboxing)
seq and $! evalute WHNF. Note that
f $! x = seq x (f x)
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Are tuples more efficient than lists in Python?
...s are incorporated directly in a tuple object. In contrast, lists have an extra layer of indirection to an external array of pointers.
This gives tuples a small speed advantage for indexed lookups and unpacking:
$ python3.6 -m timeit -s 'a = (10, 20, 30)' 'a[1]'
10000000 loops, best of 3: 0.0304 ...
Changing the size of a column referenced by a schema-bound view in SQL Server
... You can't bypass it, that's its whole purpose. Somebody went to extra length to add the schemabindig to prevent table changes. This is not some accident, looks like the person know what was doing. Are you sure you want to change the table?
– Remus Rusanu
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Creating functions in a loop
...cifically looking for early binding.
If you're worried about f getting an extra argument (and thus potentially being called erroneously), there's a more sophisticated way which involved using a closure as a "function factory":
def make_f(i):
def f():
return i
return f
and in your...
Differences between Emacs and Vim
...ared to using a GUI editor/IDE and using something like python/awk/etc for extra tasks is up to you.
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Django: Why do some model fields clash with each other?
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Sometimes you have to use extra formatting in related_name
- actually, any time when inheritance is used.
class Value(models.Model):
value = models.DecimalField(decimal_places=2, max_digits=5)
animal = models.ForeignKey(
Animal, relat...
Postgres: “ERROR: cached plan must not change result type”
...RDS Postgres 10 instance, enabling the conservative setting does result in extra CPU usage on the database server. It wasn't much though, I could only even see the autosave functionality show up as using a measurable amount of CPU after I'd tuned every single query my load test was using and starte...
What are some better ways to avoid the do-while(0); hack in C++?
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Try to extract the code into a separate function (or perhaps more than one). Then return from the function if the check fails.
If it's too tightly coupled with the surrounding code to do that, and you can't find a way to reduce the ...