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Meaning of “[: too many arguments” error from if [] (square brackets)
...t find any one simple straightforward resource spelling out the meaning of and fix for the following BASH shell error, so I'm posting what I found after researching it.
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How do I use boolean variables in Perl?
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@BlueWaldo: you can also use cmp and <=> when comparing and assigning the results of the comparison to a scalar. $var = $var1 cmp $var2; 'cmp' and '<=>' (used for numeric comparisons) returns -1, 0, or 1 if left argument is less than, equal to,...
Finding the number of days between two dates
...I think returning a negative number of days provides relevant information. And you should be using $your_date-$now, if you want a future date to return a positive integer.
– Tim
Mar 2 '12 at 18:49
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What do 'real', 'user' and 'sys' mean in the output of time(1)?
What do 'real', 'user' and 'sys' mean in the output of time?
6 Answers
6
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How to avoid isset() and empty()
I have several older applications that throw a lot of "xyz is undefined" and "undefined offset" messages when running on the E_NOTICE error level, because the existence of variables is not explicitly checked using isset() and consorts.
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Why does jQuery or a DOM method such as getElementById not find the element?
...ers parse HTML documents from top to bottom. Elements are added to the DOM and scripts are (generally) executed as they're encountered. This means that order matters. Typically, scripts can't find elements which appear later in the markup because those elements have yet to be added to the DOM.
Cons...
What are bitwise shift (bit-shift) operators and how do they work?
I've been attempting to learn C in my spare time, and other languages (C#, Java, etc.) have the same concept (and often the same operators) ...
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What's the difference between `on` and `live` or `bind`?
... vs delegate. In future versions of jQuery, these methods will be removed and only on and one will be left.
Examples:
// Using live()
$(".mySelector").live("click", fn);
// Equivalent `on` (there isn't an exact equivalent, but with good reason)
$(document).on("click", ".mySelector", fn);
// ...
delete vs delete[] operators in C++
What is the difference between delete and delete[] operators in C++?
7 Answers
7
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Custom HTTP headers : naming conventions
... posted to deprecate the recommendation of using the "X-" prefix for non-standard headers. The reason is that when non-standard headers prefixed with "X-" become standard, removing the "X-" prefix breaks backwards compatibility, forcing application protocols to support both names (E.g, x-gzip & ...