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Is there a way to instantiate objects from a string holding their class name?
...ce() { return new T; }
typedef std::map<std::string, Base*(*)()> map_type;
map_type map;
map["DerivedA"] = &createInstance<DerivedA>;
map["DerivedB"] = &createInstance<DerivedB>;
And then you can do
return map[some_string]();
Getting a new instance. Another idea is ...
Will the base class constructor be automatically called?
...ered Oct 31 '12 at 19:21
Science_FictionScience_Fiction
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...
How to convert a scala.List to a java.util.List?
...1,2,3))
From Scala 2.8 onwards:
import scala.collection.JavaConversions._
import scala.collection.mutable.ListBuffer
asList(ListBuffer(List(1,2,3): _*))
val x: java.util.List[Int] = ListBuffer(List(1,2,3): _*)
However, asList in that example is not necessary if the type expected is a Java List,...
Real world example about how to use property feature in python?
...changing terms.
Complex calculation hidden behind an attribute:
class PDB_Calculator(object):
...
@property
def protein_folding_angle(self):
# number crunching, remote server calls, etc
# all results in an angle set in 'some_angle'
# It could also reference a ca...
How do I print to the debug output window in a Win32 app?
... either maps to OutputDebugStringA(char const*) or OutputDebugStringW(wchar_t const*). In the later case you will have to supply a wide character string to the function. To create a wide character literal you can use the L prefix:
OutputDebugStringW(L"My output string.");
Normally you will use th...
Speed comparison with Project Euler: C vs Python vs Erlang vs Haskell
...
Using GHC 7.0.3, gcc 4.4.6, Linux 2.6.29 on an x86_64 Core2 Duo (2.5GHz) machine, compiling using ghc -O2 -fllvm -fforce-recomp for Haskell and gcc -O3 -lm for C.
Your C routine runs in 8.4 seconds (faster than your run probably because of -O3)
The Haskell solution runs in...
Determine function name from within that function (without using traceback)
...t want to play with the stack yourself, you should either use "bar" or bar.__name__ depending on context.
The given rejection notice is:
This PEP is rejected. It is not clear how it should be implemented or what the precise semantics should be in edge cases, and there aren't enough important us...
Difference between reduce and foldLeft/fold in functional programming (particularly Scala and Scala
...ase of foldLeft
scala> val intParList: ParSeq[Int] = (1 to 100000).map(_ => scala.util.Random.nextInt()).par
scala> timeMany(1000, intParList.reduce(_ + _))
Took 462.395867 milli seconds
scala> timeMany(1000, intParList.foldLeft(0)(_ + _))
Took 2589.363031 milli seconds
reduce vs fo...
super() fails with error: TypeError “argument 1 must be type, not classobj” when parent does not inh
...nk your python version is 2.X, the super would work when adding this code
__metaclass__ = type
so the code is
__metaclass__ = type
class B:
def meth(self, arg):
print arg
class C(B):
def meth(self, arg):
super(C, self).meth(arg)
print C().meth(1)
...
What's the dSYM and how to use it? (iOS SDK)
... 0x000000018f3c9380 closure #1 in closure #1 in closure #1 in _assertionFailure+ 217984 (_:_:file:line:flags:) + 452
1 libswiftCore.dylib 0x000000018f3c9380 closure #1 in closure #1 in closure #1 in _assertionFailure+ 217984 (_:_:file:line:flags:) + 452
2 libswiftCore.d...