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How to have jQuery restrict file types on upload?

...be bound using $("#my_upload_form").submit(function() { // above check }); api.jquery.com/submit. you can also prevent the form submitting using $("#my_upload_form").submit(function(e) { // above check e.preventDefault(); }); – Liam Sep 24 '12 at 9:50 ...
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How to ignore deprecation warnings in Python

... This doesn't work for me at all, still seeing deprecationwarnings. – user1244215 Oct 22 '13 at 0:43 9 ...
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mongodb: insert if not exists

... has built-in support for this. Pass an extra parameter to your update() call: {upsert:true}. For example: key = {'key':'value'} data = {'key2':'value2', 'key3':'value3'}; coll.update(key, data, upsert=True); #In python upsert must be passed as a keyword argument This replaces your if-find-els...
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Assign variable in if condition statement, good practice or not? [closed]

...tended to write this: if (value == someFunction()) { ... } If you really want to do the assignment in place, I would recommend doing an explicit comparison as well: if ((value = someFunction()) === <whatever truthy value you are expecting>) { ... } ...
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Why do we need message brokers like RabbitMQ over a database like PostgreSQL?

...ustering options are also available. In regards to AMQP, I would say a really cool feature is the "exchange", and the ability for it to route to other exchanges. This gives you more flexibility and enables you to create a wide array of elaborate routing typologies which can come in very handy when...
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Origin is not allowed by Access-Control-Allow-Origin

... of the responding server is to add a response header for: Access-Control-Allow-Origin: * This will allow cross-domain Ajax. In PHP, you'll want to modify the response like so: <?php header('Access-Control-Allow-Origin: *'); ?> You can just put the Header set Access-Control-Allow-Origin ...
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How do I copy a hash in Ruby?

...Clone is a method on Object, BTW, so everything has access to it. See the API details here – Dylan Lacey Aug 28 '12 at 2:55 ...
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What is the difference between named and positional parameters in Dart?

...ss the similarities. Dart's optional parameters are optional in that the caller isn't required to specify a value for the parameter when calling the function. Optional parameters can only be declared after any required parameters. Optional parameters can have a default value, which is used when a...
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Why can't I forward-declare a class in a namespace using double colons?

... All other answers were confusing to me but this "you can't declare a class within a namespace from outside that namespace. You have to be in the namespace." was very helpful hint to remember. – dashesy ...
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Iterating Over Dictionary Key Values Corresponding to List in Python

...ict (league) itself, or league.keys(): for team in league.keys(): runs_scored, runs_allowed = map(float, league[team]) You can also iterate over both the keys and the values at once by iterating over league.items(): for team, runs in league.items(): runs_scored, runs_allowed = map(float,...