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How to test if parameters exist in rails
...re asking about existence. You might need to differentiate:
Not there at all.
There but nil.
There but false.
There but an empty string.
as well. Hard to say without more details of your precise situation.
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How to specify test directory for mocha?
...le hierarchy than the rest of the tests, and would only find that one odd ball file and not the dozen others that lived on the same level in the hierarchy. Wrapping in quotes fixed it.
– Stoutie
Nov 9 '15 at 0:23
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How to delete files/subfolders in a specific directory at the command prompt in Windows
Say, there is a variable called %pathtofolder% , as it makes it clear it is a full path of a folder.
15 Answers
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Why isn't SQL ANSI-92 standard better adopted over ANSI-89?
...n years after it was approved, it's about time people start using it! And all brands of SQL database now support it, so there's no reason to continue to use the nonstandard (+) Oracle syntax or *= Microsoft/Sybase syntax.
As for why it's so hard to break the developer community of the SQL-89 habit...
What is /dev/null 2>&1?
... either appending to or writing to /dev/null has the same net effect. I usually just use > for that reason.)
2>&1 redirects standard error (2) to standard output (1), which then discards it as well since standard output has already been redirected.
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Is there “0b” or something similar to represent a binary number in Javascript
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Update:
Newer versions of JavaScript -- specifically ECMAScript 6 -- have added support for binary (prefix 0b), octal (prefix 0o) and hexadecimal (prefix: 0x) numeric literals:
var bin = 0b1111; // bin will be set to 15
var oct = 0o17; // oct will be set to 15
var...
Working with huge files in VIM
I tried opening a huge (~2GB) file in VIM but it choked. I don't actually need to edit the file, just jump around efficiently.
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What are the effects of exceptions on performance in Java?
Question: Is exception handling in Java actually slow?
18 Answers
18
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Regex for numbers only
I haven't used regular expressions at all, so I'm having difficulty troubleshooting. I want the regex to match only when the contained string is all numbers; but with the two examples below it is matching a string that contains all numbers plus an equals sign like "1234=4321". I'm sure there's a way...
jquery get all form elements: input, textarea & select
Is there an easy way (without listing them all separately) in jquery to select all form elements and only form elements.
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