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Testing for empty or nil-value string [duplicate]

I'm trying to set a variable conditionally in Ruby. I need to set it if the variable is nil or empty (0 length string). I've come up with the following: ...
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Link to “pin it” on pinterest without generating a button

... or hundreds of posts, each one with social buttons. I just can't generate all the buttons for each url: it is too slow (facebook, g+, twitter, pinterest... for hundreds of links). So, instead of the facebook share button to be generated on the fly, I use a simple img pointing to ...
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How to assign from a function which returns more than one value?

...eturningTwoValues() If you only need the first or second component these all work too: list[a] <- functionReturningTwoValues() list[a, ] <- functionReturningTwoValues() list[, b] <- functionReturningTwoValues() (Of course, if you only needed one value then functionReturningTwoValues()[...
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T-SQL: Deleting all duplicate rows but keeping one [duplicate]

...up identifier and "baz" is some sort of time stamp. In order to keep the latest, you'd do ORDER BY baz desc) share | improve this answer | follow | ...
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Is there a performance gain in using single quotes vs double quotes in ruby?

... Can you add << to this test? – Nick Aug 28 '13 at 13:07 add a comment  |  ...
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&& (AND) and || (OR) in IF statements

...ill not be evaluated. And this is very useful. For example, if you need to test whether a String is not null or empty, you can write: if (str != null && !str.isEmpty()) { doSomethingWith(str.charAt(0)); } or, the other way around if (str == null || str.isEmpty()) { complainAboutUnusa...
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How to validate date with format “mm/dd/yyyy” in JavaScript?

...ut string is a valid date formatted as "mm/dd/yyyy" function isValidDate(dateString) { // First check for the pattern if(!/^\d{1,2}\/\d{1,2}\/\d{4}$/.test(dateString)) return false; // Parse the date parts to integers var parts = dateString.split("/"); var day = parseInt...
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Windows 7 SDK installation failure

I seem to be completely unable to install the Windows 7 SDK onto my machine, and the only solution I've found on the web is to make a swathe of registry changes. I've done this - still no success. ...
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How to include file in a bash shell script

... use of File color.sh does not error but, the color do not display. I have tested this in Ubuntu 18.04 and the Bash version is: GNU bash, version 4.4.19(1)-release (x86_64-pc-linux-gnu) share | imp...
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What is the argument for printf that formats a long?

... Actually, you should change it to be %ld, to be more harmonic with OP question. – DrBeco Jun 21 '15 at 5:28 ...