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Aren't Python strings immutable? Then why does a + “ ” + b work?
...the variable a to point at a new string "Dog eats treats". You didn't actually mutate the string "Dog". Strings are immutable, variables can point at whatever they want.
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Adding a new value to an existing ENUM Type
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It's worth mentioning that this can all be done in a single transaction, so it's mostly safe to do it in a production database.
– David Leppik
Jul 8 '11 at 20:41
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Timeout for python requests.get entire response
...As long as you don't set stream=True on that request, this will cause the call to requests.get() to timeout if the connection takes more than ten seconds, or if the server doesn't send data for more than ten seconds.
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In where shall I use isset() and !empty()
... it's not a good idea to use this operator for math in case "0" is accidentally a string. This can be dangerous. Instead, use basic >, < and == operators and convert variables using intval() or floatval().
– kaleazy
Feb 14 at 18:08
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Viewing all defined variables [duplicate]
...ython shell. What I want to have is Matlab style listout where you can see all the variables that have been defined up to a point (so I know which names I've used, their values and such).
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C++ equivalent of java's instanceof
...nceof) you'd better ask yourself whether it's a necessary thing. It's generally a sign of poor design.
Typical workarounds is putting the special behaviour for the class you are checking for into a virtual function on the base class or perhaps introducing something like a visitor where you can int...
Difference between Node object and Element object?
I am totally confused between Node object and Element object.
document.getElementById() returns Element object while document.getElementsByClassName()
returns NodeList object(Collection of Elements or Nodes?)
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Representing and solving a maze given an image
...lection breaks are not false edges introduced by wrong threshold. In fact, all interior points of this maze are accessible from the start.
Add artificial borders on the maze to make sure virtual traveler will not walk around it :)
Implement breadth-first search (BFS) in your favorite language and ru...
What does the Ellipsis object do?
While idly surfing the namespace I noticed an odd looking object called Ellipsis , it does not seem to be or do anything special, but it's a globally available builtin.
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Is it possible to forward-declare a function in Python?
...rwards is impossible, what about defining it in some other module?
Technically you still define it first, but it's clean.
You could create a recursion like the following:
def foo():
bar()
def bar():
foo()
Python's functions are anonymous just like values are anonymous, yet they can be ...