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Why are empty catch blocks a bad idea? [closed]
...-catch , which people (including Jon Skeet) say empty catch blocks are a really bad idea? Why this? Is there no situation where an empty catch is not a wrong design decision?
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php is null or empty?
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As is shown in the following table, empty($foo) is equivalent to $foo==null and is_null($foo) has the same function of $foo===null. The table also shows some tricky values regarding the null comparison. (ϕ denotes an uninitialized variables. )
empty is_n...
Environment variable substitution in sed
...tement more readable and less error prone).
So if you want to search for 'foo' and replace it with the content of $BAR, you can enclose the sed command in double-quotes.
sed 's/foo/$BAR/g'
sed "s/foo/$BAR/g"
In the first, $BAR will not expand correctly while in the second $BAR will expand correc...
What is more efficient? Using pow to square or just multiply it with itself?
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I tested the performance difference between x*x*... vs pow(x,i) for small i using this code:
#include <cstdlib>
#include <cmath>
#include <boost/date_time/posix_time/posix_time.hpp>
inline boost::posix_time::ptime now()
{
return boost::posix_time::microsec_clock::local_t...
Turn off textarea resizing
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Try this CSS to disable resizing
The CSS to disable resizing for all textareas looks like this:
textarea {
resize: none;
}
You could instead just assign it to a single textarea by name (where the textarea HTML is ):
textarea[name=foo] {
resize: none;
}
Or by id (where the tex...
Get property value from string using reflection
...fferentiate between a null value of an existing property or no property at all? I'd much rather know immediately that I was sending in a bad property name. This is not production code, but a better improvement would be to throw a more specific exception (e.g. check for null on GetProperty and throw ...
Function overloading by return type?
Why don't more mainstream statically typed languages support function/method overloading by return type? I can't think of any that do. It seems no less useful or reasonable than supporting overload by parameter type. How come it's so much less popular?
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final keyword in method parameters [duplicate]
...them to methods. This means the final doesn't mean any difference for the calling code. This only means that inside the method the variables can not be reassigned. (note that if you have a final object, you can still change the attributes of the object).
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Using global variables in a function
...ce global variables are so dangerous, Python wants to make sure that you really know that's what you're playing with by explicitly requiring the global keyword.
See other answers if you want to share a global variable across modules.
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How to indicate param is optional using inline JSDoc?
...fficial documentation:
Optional parameter
An optional parameter named foo.
@param {number} [foo]
// or:
@param {number=} foo
An optional parameter foo with default value 1.
@param {number} [foo=1]
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