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Why is lazy evaluation useful?
... You can actually emulate an infinite list in Python using generators and generator expressions (which work in a similar way to a list comprehension): python.org/doc/2.5.2/ref/genexpr.html
– John Montgomery
Nov 5 '08 at 15:11
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how to delete all cookies of my website in php
...ferent domain settings. One of them will make it into the $_COOKIE array, and the other won't. But they will both be visible in HTTP_COOKIE. If you want to clean this situation up, this is the way to do it.
– dlo
Jun 10 '15 at 13:08
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What is the best way to implement nested dictionaries?
...ython?
This is a bad idea, don't do it. Instead, use a regular dictionary and use dict.setdefault where apropos, so when keys are missing under normal usage you get the expected KeyError. If you insist on getting this behavior, here's how to shoot yourself in the foot:
Implement __missing__ on a di...
How do I check if a SQL Server text column is empty?
I am using SQL Server 2005. I have a table with a text column and I have many rows in the table where the value of this column is not null, but it is empty. Trying to compare against '' yields this response:
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How do I check if I'm running on Windows in Python? [duplicate]
I found the platform module but it says it returns 'Windows' and it's returning 'Microsoft' on my machine. I notice in another thread here on stackoverflow it returns 'Vista' sometimes.
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Using print statements only to debug
I have been coding a lot in Python of late. And I have been working with data that I haven't worked with before, using formulae never seen before and dealing with huge files. All this made me write a lot of print statements to verify if it's all going right and identify the points of failure. But, ...
How many random elements before MD5 produces collisions?
... quintillion 374 quadrillion 607 trillion 431 billion 768 million 211 thousand 456.
However if you keep all the hashes then the probability is a bit higher thanks to birthday paradox. To have a 50% chance of any hash colliding with any other hash you need 264 hashes. This means that to get a collis...
Why does pattern matching in Scala not work with variables?
...sense that the default behaviour is for lowercase patterns to be variables and not stable identifiers. Only when you see something beginning with upper case, or in back ticks, do you need to be aware that it comes from the surrounding scope.
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Android Fatal signal 11 (SIGSEGV) at 0x636f7d89 (code=1). How can it be tracked down?
...the other posts on tracking down the reasons for getting a SIGSEGV in an Android app. I plan to scour my app for possible NullPointers related to Canvas use, but my SIGSEGV barfs up a different memory address each time. Plus I've seen code=1 and code=2 . If the memory address was 0x00000000 ...
What does 'useLegacyV2RuntimeActivationPolicy' do in the .NET 4 config?
While converting a project that used SlimDX, and therefore has unmanaged code, to .NET 4.0 I ran into the following error:
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