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Uncaught ReferenceError: jQuery is not defined [duplicate]
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What is jQuery is the first script on the page and there is an error anyway?
– Green
Jul 29 '13 at 3:33
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Counting the occurrences / frequency of array elements
In Javascript, I'm trying to take an initial array of number values and count the elements inside it. Ideally, the result would be two new arrays, the first specifying each unique element, and the second containing the number of times each element occurs. However, I'm open to suggestions on the form...
Block comments in html.erb templates in rails
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The =begin approach is annoying because:
It doesn't work for mixed HTML and Ruby (or just HTML) that's on a single line
It's annoying to type
The <% if false %> approach works, but it looks weird and doesn't give anyone else who looks at your code a hint about your intentions.
My solutio...
Painless way to install a new version of R?
Andrew Gelman recently lamented the lack of an easy upgrade process for R (probably more relevant on Windows than Linux). Does anyone have a good trick for doing the upgrade, from installing the software to copying all the settings/packages over?
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How to check if a file exists in Documents folder?
... if it was a main application you'll have access to the entire file system and you'll use the shared Documents directory. If you install it via iTunes or XCode you'll be using your applications' personal directory. It's nice to store files in your local directory for backup purposes.
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Bash/sh - difference between && and ;
I normally use ; to combine more than one command in a line, but some people prefer && . Is there any difference? For example, cd ~; cd - and cd ~ && cd - seems to make the same thing. What version is more portable, e.g. will be supported by a bash-subset like Android's shell ...
Create Directory When Writing To File In Node.js
I've been tinkering with Node.js and found a little problem. I've got a script which resides in a directory called data . I want the script to write some data to a file in a subdirectory within the data subdirectory. However I am getting the following error:
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What is the correct value for the disabled attribute?
...the valid markup.
For HTML5, <input type="text" disabled /> is valid and used by W3C on their samples.
In fact, both ways works on all major browsers.
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CORS: Cannot use wildcard in Access-Control-Allow-Origin when credentials flag is true
...these questions :
Access-Control-Allow-Origin wildcard subdomains, ports and protocols
Cross Origin Resource Sharing with Credentials
Besides * is too permissive and would defeat use of credentials. So set http://localhost:3000 or http://localhost:8000 as the allow origin header.
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What is the difference between t.belongs_to and t.references in rails?
What is the difference between t.references and t.belongs_to ?
Why are we having those two different words? It seems to me they do the same thing?
Tried some Google search, but find no explanation.
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