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In where shall I use isset() and !empty()
... it's not a good idea to use this operator for math in case "0" is accidentally a string. This can be dangerous. Instead, use basic >, < and == operators and convert variables using intval() or floatval().
– kaleazy
Feb 14 at 18:08
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How to make a variadic macro (variable number of arguments)
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The reason for ## before VA_ARGS is that it swallows the preceding comma in case the variable-argument list is empty, eg. FOO("a") expands to printf("a"). This is an extension of gcc (and vc++, maybe), C99 requires at least one argument to be present in place of the elli...
ARC and bridged cast
...__bridge_transfer? Otherwise it would seem that the moment CFRelease() is called the object is gone and points to nothing. Similarly, when you use __bridge_retain, does ARC reduce the op's retain count by 1? Else it seems that the object would never be properly released.
– Tony...
What does the Ellipsis object do?
While idly surfing the namespace I noticed an odd looking object called Ellipsis , it does not seem to be or do anything special, but it's a globally available builtin.
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C++ equivalent of java's instanceof
...nceof) you'd better ask yourself whether it's a necessary thing. It's generally a sign of poor design.
Typical workarounds is putting the special behaviour for the class you are checking for into a virtual function on the base class or perhaps introducing something like a visitor where you can int...
Good example of livelock?
...ontinue;
}
// Spouse wasn't hungry, so finally eat
spoon.use();
isHungry = false;
System.out.printf(
"%s: I am stuffed, my darling %s!%n",
name, spouse.getName());...
Bring element to front using CSS
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I don't really remember the circumstances of my question clearly, but my problem was, that I understood what z-index does, but still it did not work. What I have learned from this answer is, that with z-index you have to take into cons...
Autoreload of modules in IPython [duplicate]
Is there a way to have IPython automatically reload all changed code? Either before each line is executed in the shell or failing that when it is specifically requested to. I'm doing a lot of exploratory programming using IPython and SciPy and it's quite a pain to have to manually reload each module...
How do I create a multiline Python string with inline variables?
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This isn't really the same because the OP wants named parameters, not positional ones.
– Ismail Badawi
Apr 11 '12 at 19:33
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Aren't Python strings immutable? Then why does a + “ ” + b work?
...the variable a to point at a new string "Dog eats treats". You didn't actually mutate the string "Dog". Strings are immutable, variables can point at whatever they want.
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