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What does Python's eval() do?
...less until you find a need for it. It is used on sites like codepad.org to allow you to execute scripts in a test environment. eval() can also be used to execute highly-dynamic code, but you should make yourself fully aware of the security and performance risks before using it.
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Declaring variables inside or outside of a loop
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The scope of local variables should always be the smallest possible.
In your example I presume str is not used outside of the while loop, otherwise you would not be asking the question, because declaring it inside the while loop would not be an option, since it would not comp...
Reading output of a command into an array in Bash
...tput of a command in an array, with one line per element, there are essentially 3 ways:
With Bash≥4 use mapfile—it's the most efficient:
mapfile -t my_array < <( my_command )
Otherwise, a loop reading the output (slower, but safe):
my_array=()
while IFS= read -r line; do
my_array+...
Is .NET/Mono or Java the better choice for cross-platform development? [closed]
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Well....Java is actually more portable. Mono isn't implemented everywhere, and it lags behind the Microsoft implementation significantly. The Java SDK seems to stay in better sync across platforms (and it works on more platforms).
I'd also ...
How to send data to local clipboard from a remote SSH session
... to a linux server via SSH. Like the OP, I wanted to be able to transfer small bits of text from terminal to my local clipboard, using only the keyboard.
The essence of the solution:
commandThatMakesOutput | ssh desktop pbcopy
When run in an ssh session to a remote computer, this command takes...
How to add property to a class dynamically?
...ing on. Better late than never.
You can add a property to a class dynamically. But that's the catch: you have to add it to the class.
>>> class Foo(object):
... pass
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>>> foo = Foo()
>>> foo.a = 3
>>> Foo.b = property(lambda self: self.a + 1)
>>&...
Difference between TCP and UDP?
...TCP is a connection oriented stream over an IP network. It guarantees that all sent packets will reach the destination in the correct order. This imply the use of acknowledgement packets sent back to the sender, and automatic retransmission, causing additional delays and a general less efficient tra...
Doctrine - How to print out the real sql, not just the prepared statement?
...trine is not sending a "real SQL query" to the database server : it is actually using prepared statements, which means :
Sending the statement, for it to be prepared (this is what is returned by $query->getSql())
And, then, sending the parameters (returned by $query->getParameters())
and exe...
What's the difference between a proc and a lambda in Ruby?
...ept the resulting Proc objects check the number of parameters passed when called.
An example:
p = Proc.new {|a, b| puts a**2+b**2 } # => #<Proc:0x3c7d28@(irb):1>
p.call 1, 2 # => 5
p.call 1 # => NoMethodError: undefined method `**' for nil:NilClass
p.call 1, 2, 3 # => 5
l = lamb...
How can I handle time zones in my webapp?
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The majority of your users probably will not change timezones much, or at all. For the most part, the situation you outlined is uncommon. By implementing a dropdown with a suitable default, you should be able to make things easy enough for those who do move around (because they typically have a bet...