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How do I test if a variable is a number in Bash?
...[ $yournumber =~ $re ]] ; then
echo "error: Not a number" >&2; exit 1
fi
If the value is not necessarily an integer, consider amending the regex appropriately; for instance:
^[0-9]+([.][0-9]+)?$
...or, to handle numbers with a sign:
^[+-]?[0-9]+([.][0-9]+)?$
...
How to dynamically create CSS class in JavaScript and apply?
...need to create a CSS stylesheet class dynamically in JavaScript and assign it to some HTML elements like - div, table, span, tr, etc and to some controls like asp:Textbox, Dropdownlist and datalist.
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PHP Fatal error: Cannot redeclare class
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It means you've already created a class.
For instance:
class Foo {}
// some code here
class Foo {}
That second Foo would throw the error.
share...
Php multiple delimiters in explode
... a problem, I have a string array, and I want to explode in different delimiter. For Example
12 Answers
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Is it possible to make a div 50px less than 100% in CSS3? [duplicate]
Is it possible to make a div 50px less than 100% in pure CSS? I want the <div> to be only 50px less than 100%. I don't want any JavaScript.
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Where to put Gradle configuration (i.e. credentials) that should not be committed?
...follow
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edited Oct 24 '15 at 5:24
mkobit
31.3k77 gold badges124124 silver badges129129 bronze badges
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How do you remove duplicates from a list whilst preserving order?
...alling seen.add? Python is a dynamic language, and resolving seen.add each iteration is more costly than resolving a local variable. seen.add could have changed between iterations, and the runtime isn't smart enough to rule that out. To play it safe, it has to check the object each time.
If you pla...
How do you echo a 4-digit Unicode character in Bash?
...ES' (U+2620)), but I can't figure out the magic incantation to make echo spit it, or any other, 4-digit Unicode character. Two-digit one's are easy. For example, echo -e "\x55", .
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In C# what is the difference between ToUpper() and ToUpperInvariant()?
...log post.
I wouldn't be surprised to hear that there are various other capitalization issues around elided characters etc. This is just one example I know off the top of my head... partly because it bit me years ago in Java, where I was upper-casing a string and comparing it with "MAIL". That didn'...
How to deal with SettingWithCopyWarning in Pandas?
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The SettingWithCopyWarning was created to flag potentially confusing "chained" assignments, such as the following, which does not always work as expected, particularly when the first selection returns a copy. [see GH5390 and GH5597 for ...