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Where to define custom error types in Ruby and/or Rails?
... error types in a Ruby library (gem) or Ruby on Rails application? Specifically:
5 Answers
...
Razor-based view doesn't see referenced assemblies
...m another project in the same solution (with assembly name MyCoreDBLayer). All objects from MyCore.DBLayer worked perfectly in Controllers and Models but failed in Razor views with an error 'The type or namespace name 'DBLayer' does not exist in the namespace 'MyCore' (are you missing an assembly re...
When is std::weak_ptr useful?
...want to keep them in memory, so you hold a strong pointer to them. Periodically, you scan the cache and decide which objects have not been accessed recently. You don't need to keep those in memory, so you get rid of the strong pointer.
But what if that object is in use and some other code holds a s...
How to overcome TypeError: unhashable type: 'list'
...used to compare dictionary keys during a dictionary lookup quickly.
Internally, hash() method calls __hash__() method of an object which are set by default for any object.
Converting a nested list to a set
>>> a = [1,2,3,4,[5,6,7],8,9]
>>> set(a)
Traceback (most recent call last...
Is it true that one should not use NSLog() on production code?
... line number to make it easier to track down log statements.
#define DEBUG_MODE
#ifdef DEBUG_MODE
#define DebugLog( s, ... ) NSLog( @"<%p %@:(%d)> %@", self, [[NSString stringWithUTF8String:__FILE__] lastPathComponent], __LINE__, [NSString stringWithFormat:(s), ##__VA_ARGS__] )
#else
...
Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
...scientific application. One thing I noticed is that GCC will optimize the call pow(a,2) by compiling it into a*a , but the call pow(a,6) is not optimized and will actually call the library function pow , which greatly slows down the performance. (In contrast, Intel C++ Compiler , executable ...
Is there a way to 'uniq' by column?
...o you need the ,1 in -k1,1? why not just -k1?
– hello_there_andy
Nov 24 '14 at 20:10
19
@hello_th...
How to make a Python script run like a service or daemon in Linux
...ass the Daemon class and override the run() method
"""
def __init__(self, pidfile, stdin='/dev/null', stdout='/dev/null', stderr='/dev/null'):
self.stdin = stdin
self.stdout = stdout
self.stderr = stderr
self.pidfile = p...
Could not load NIB in bundle
...
Additionally, if you are using alloc init, instead of initWithNibName:bunle:, what you will get is a black screen.
– Robert Childan
Apr 20 '12 at 8:36
...
Check if a number is int or float
...>> if isinstance(x, int):
print 'x is a int!'
x is a int!
_EDIT:_
As pointed out, in case of long integers, the above won't work. So you need to do:
>>> x = 12L
>>> import numbers
>>> isinstance(x, numbers.Integral)
True
>>> isinstance(x, int)
F...