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How can I add new keys to a dictionary?

... value is in the end too. Anyway answer has been edited and is much better now. Updating with a dictionary is good when it's likely that it contains many items. – Jean-François Fabre♦ Jan 20 at 16:26 ...
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brew install mysql on macOS

... Because this thread is old, the "launchctl unload" line above is now wrong. The file homebrew installs is not longer called "com.mysql.mysqld.plist", it is called "homebrew.mxcl.mysql.plist". The line should now read "launchctl unload -w ~/Library/LaunchAgents/homebrew.mxcl.mysql.plist" ...
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rails - Devise - Handling - devise_error_messages

...e method, effectively overriding the default implementation. I'll let you know how it goes. Update Yep, that works. I created app/helpers/devise_helper.rb and overrode it like so: module DeviseHelper def devise_error_messages! 'KABOOM!' end end So knowing this, I can modify the method t...
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JavaScript by reference vs. by value [duplicate]

...false Example 2: var a = ["1", "2", {foo:"bar"}]; var b = a[1]; // b is now "2"; var c = a[2]; // c now references {foo:"bar"} a[1] = "4"; // a is now ["1", "4", {foo:"bar"}]; b still has the value // it had at the time of assignment a[2] = "5"; // a is now ["1", "4", "5"]; c st...
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How to find and turn on USB debugging mode on Nexus 4

...he Menu button while on your home screen and tapping “System settings” Now scroll to the bottom and tap “About phone” or “About tablet”. At the “About” screen, scroll to the bottom and tap on “Build number” seven times. Make sure you tap seven times. If you see a “Not need, ...
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How can I check for “undefined” in JavaScript? [duplicate]

...n window; // true "theFoo" in window; // false If you are interested in knowing whether the variable hasn't been declared or has the value undefined, then use the typeof operator, which is guaranteed to return a string: if (typeof myVar !== 'undefined') Direct comparisons against undefined are ...
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What is this Javascript “require”?

...b browser with a limited global context defined mostly by what came to be known as the Document Object Model (DOM) level 0 (the Netscape Navigator Javascript API). Server-side Javascript eliminates that restriction and allows Javascript to call into various pieces of native code (like the Postgres ...
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PHP Pass by reference in foreach [duplicate]

... the output I was able to understand: $v gets the item [0](zero). $a[3] is now zero $v gets the item [1](one). $a[3] is now one $v gets the item [2](two). $a[3] is now two $v gets the item [3](two). $a[3] is now two – Eduardo Sep 2 '13 at 2:18 ...
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How can I use NSError in my iPhone App?

...ies) { // sad, we can't solve world hunger, but we can let people know what went wrong! // init dictionary to be used to populate error object NSMutableDictionary* details = [NSMutableDictionary dictionary]; [details setValue:@"ran out of money" forKey:NSLocalizedDesc...
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Is there a MySQL option/feature to track history of changes to records?

...ing relatively painless to implement - your existing code doesn't need to know about the triggers and audit stuff. If the business requirement is "show me what the state of the data was on a given date in the past", it means that the aspect of change over time has entered your solution. Whilst you...