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What is the difference between Ruby 1.8 and Ruby 1.9
...m not clear on the differences between the "current" version of Ruby (1.8) and the "new" version (1.9). Is there an "easy" or a "simple" explanation of the differences and why it is so different?
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Is calculating an MD5 hash less CPU intensive than SHA family functions?
Is calculating an MD5 hash less CPU intensive than SHA-1 or SHA-2 on "standard" laptop x86 hardware? I'm interested in general information, not specific to a certain chip.
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What's a concise way to check that environment variables are set in a Unix shell script?
...(an empty string) is OK — not exactly what you want, but the alternative and older notation.
The second variant (using :?) requires DEST to be set and non-empty.
If you supply no message, the shell provides a default message.
The ${var?} construct is portable back to Version 7 UNIX and the Bourne ...
Alphabet range in Python
...', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z']
And to do it with range
>>> list(map(chr, range(97, 123))) #or list(map(chr, range(ord('a'), ord('z')+1)))
['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v...
Usage of sys.stdout.flush() method
...
Python's standard out is buffered (meaning that it collects some of the data "written" to standard out before it writes it to the terminal). Calling sys.stdout.flush() forces it to "flush" the buffer, meaning that it will write everythi...
Check whether a variable is a string in Ruby
...
I think you are looking for instance_of?. is_a? and kind_of? will return true for instances from derived classes.
class X < String
end
foo = X.new
foo.is_a? String # true
foo.kind_of? String # true
foo.instance_of? String # false
foo.instance_of? X ...
Why does this (null || !TryParse) conditional result in “use of unassigned local variable”?
...se, so I'm set for now. Thanks for your insight!
– Brandon Martinez
Apr 30 '13 at 17:39
4
@NominS...
std::back_inserter for a std::set?
...f an element is determined by the comparator of the set. Use std::inserter and pass it .begin():
std::set<int> s1, s2;
s1 = getAnExcitingSet();
transform(s1.begin(), s1.end(),
std::inserter(s2, s2.begin()), ExcitingUnaryFunctor());
The insert iterator will then call s2.insert(s2....
Interfacing with structs and anonymous unions with c2hs
... postfix: "",
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Can you create nested WITH clauses for Common Table Expressions?
...wered Sep 11 '09 at 22:12
David AndresDavid Andres
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