大约有 47,000 项符合查询结果(耗时:0.0465秒) [XML]

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How do I use boolean variables in Perl?

... @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,...
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Meaning of -

I am new to XML and I am trying to understand the basics. I read the line below in "Learning XML", but it is still not clear, for me. Can someone point me to a book or website which explains these basics clearly? ...
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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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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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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...
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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 & ...
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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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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); // ...
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Does PostgreSQL support “accent insensitive” collations?

...r now This approach is more efficient as other solutions floating around, and safer. Create an IMMUTABLE SQL wrapper function executing the two-parameter form with hard-wired schema-qualified function and dictionary. Since nesting a non-immutable function would disable function inlining, base it o...