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Why is there no xrange function in Python3?
...Some performance measurements, using timeit instead of trying to do it manually with time.
First, Apple 2.7.2 64-bit:
In [37]: %timeit collections.deque((x for x in xrange(10000000) if x%4 == 0), maxlen=0)
1 loops, best of 3: 1.05 s per loop
Now, python.org 3.3.0 64-bit:
In [83]: %timeit collec...
Is there an IDictionary implementation that, on missing key, returns the default value instead of th
...
Indeed, that won't be efficient at all.
You could always write an extension method:
public static TValue GetValueOrDefault<TKey,TValue>
(this IDictionary<TKey, TValue> dictionary, TKey key)
{
TValue ret;
// Ignore return value
dic...
MongoDB/Mongoose querying at a specific date?
...onents. To query those times you need to create a date range that includes all moments in a day.
db.posts.find( //query today up to tonight
{"created_on": {"$gte": new Date(2012, 7, 14), "$lt": new Date(2012, 7, 15)}})
s...
Undefined symbols for architecture arm64
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If your Architectures and Valid Architectures are all right, you may check whether you have added $(inherited) , which will add linker flags generated in pods, to Other Linker Flags as below:
share...
Best way to iterate through a Perl array
...ay elements occurs. ($_ is aliased to the element in #1, but #2 and #3 actually copy the scalars from the array.)
#5 might be similar.
In terms memory usage: They're all the same except for #5.
for (@a) is special-cased to avoid flattening the array. The loop iterates over the indexes of the array...
This type of CollectionView does not support changes to its SourceCollection from a thread different
...); but it is giving syntax error. Look like Send method is expecting some callback method name. I have tried various options like delegate with parameter but it is not allowing to have my custom parameter. I am very new to this kind of syntax, so it would really helpful if you can provide me synta...
Is bool a native C type?
... in the current C - C99, but not in C89/90.
In C99 the native type is actually called _Bool, while bool is a standard library macro defined in stdbool.h (which expectedly resolves to _Bool). Objects of type _Bool hold either 0 or 1, while true and false are also macros from stdbool.h.
Note, BTW, t...
Export specific rows from a PostgreSQL table as INSERT SQL script
....5.3, and my create statement was the same as yours except create view.... All I get in the output is the usual pg_dump comments and SET statements. Not sure where I'm going wrong.
– poshest
Nov 20 '16 at 15:19
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What is the difference between shallow copy, deepcopy and normal assignment operation?
...ble towards the existing object. The docs explain the difference between shallow and deep copies:
The difference between shallow and deep copying is only relevant for
compound objects (objects that contain other objects, like lists or
class instances):
A shallow copy constructs a new...
Why does javascript replace only first instance when using replace? [duplicate]
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You need to set the g flag to replace globally:
date.replace(new RegExp("/", "g"), '')
// or
date.replace(/\//g, '')
Otherwise only the first occurrence will be replaced.
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