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Haskell error parse error on input `='
...You don't explain polynomial products to a kid learning the multiplication table -- it doesn't show how much you know, it shows you don't know how to share what you do know.
– btk
Jan 27 '13 at 19:09
...
Why does running the Flask dev server run itself twice?
...g is the library that supplies Flask with the development server when you call app.run().
See the restart_with_reloader() function code; your script is run again with subprocess.call().
If you set use_reloader to False you'll see the behaviour go away, but then you also lose the reloading function...
Add custom messages in assert?
...rk; they’re compile-time constants and their use in this context is trivially optimized away. There is no runtime cost.
– zneak
Aug 9 '19 at 8:46
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Nested classes' scope?
...e will use that object the next time it is executed.)
If you instead want all Inner objects to have a reference to an Outer because outer_var is really an instance attribute:
class Outer(object):
def __init__(self):
self.outer_var = 1
def get_inner(self):
return self.Inner...
AttributeError: 'module' object has no attribute 'tests'
...
I finally figured it out working on another problem. The problem was that my test couldn't find an import.
It looks like you get the above error if your test fails to import. This makes sense because the test suite can't import ...
undefined reference to boost::system::system_category() when compiling
...raries. I have the 1.46-dev Boost libraries from the Ubuntu Repository installed, but I get an error when compiling the program.
...
Are lists thread-safe?
... data is not protected. For example:
L[0] += 1
is not guaranteed to actually increase L[0] by one if another thread does the same thing, because += is not an atomic operation. (Very, very few operations in Python are actually atomic, because most of them can cause arbitrary Python code to be call...
Cannot kill Python script with Ctrl-C
...you can't do anything with it after it exits. The process will finish when all non-daemon threads have finished; parent-child relationships don't come into that.
– Thomas K
Dec 6 '13 at 22:22
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Why can't (or doesn't) the compiler optimize a predictable addition loop into a multiplication?
...
The compiler can't generally transform
for (int c = 0; c < arraySize; ++c)
if (data[c] >= 128)
for (int i = 0; i < 100000; ++i)
sum += data[c];
into
for (int c = 0; c < arraySize; ++c)
if (data[c] >= 12...
class
...lass << foo syntax opens up foo's singleton class (eigenclass). This allows you to specialise the behaviour of methods called on that specific object.
a = 'foo'
class << a
def inspect
'"bar"'
end
end
a.inspect # => "bar"
a = 'foo' # new object, new singleton class
a.insp...