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Using port number in Windows host file

...do what you want with generic OS-level configuration - the browser is what selects the port to choose. So use bookmarks or something like that. (Some firewall/routing software might allow outbound port redirection, but that doesn't really sound like an appealing option for this.) ...
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Drawing an image from a data URL to a canvas

... in javascript , using jquery for canvas id selection : var Canvas2 = $("#canvas2")[0]; var Context2 = Canvas2.getContext("2d"); var image = new Image(); image.src = "images/eye.jpg"; Context2.drawImage(image, 0, 0); html5: <canv...
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mongodb: insert if not exists

...what data you want to write: data = {"$set":{"key2":"value2"}} Now your selected document will update the value of "key2" only and leave everything else untouched. share | improve this answer ...
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How to access random item in list?

... isn't repeated? Let's say I wanted to shuffle a deck of cards by randomly selecting one at a time, but obviously can't select the same card twice. – AdamMc331 Sep 21 '14 at 5:26 7...
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How to get an object's properties in JavaScript / jQuery?

...ct. Even most of those primitives are actually also objects with a limited selection of methods. They are cast into objects under the hood, when required. To know the base class name, you may invoke the Object.prototype.toString method on an object, like this: alert(Object.prototype.toString.call([...
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How can I calculate the number of lines changed between two commits in git?

...2> but you can use --numstat or --shortstat as well. git log can also select commits in a variety other ways - have a look at the documentation. You might be interested in things like --since (rather than specifying commit ranges, just select commits since last week) and --no-merges (merge comm...
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How to calculate the SVG Path for an arc (of a circle)

...so far, there are actually four arcs that could be drawn, so the two flags select one of them. I'm guessing you probably want to draw a small arc (meaning large-arc-flag=0), in the direction of decreasing angle (meaning sweep-flag=0). All together, the SVG path is: M 200 175 A 25 25 0 0 0 182.322 2...
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How to remove “disabled” attribute using jQuery?

... { $(".share_dependent_block input, .share_dependent_block select").prop("disabled",false); } else { $(".share_dependent_block input, .share_dependent_block select").prop("disabled",true); } } ); }); ...
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Rails where condition using NOT NIL

..., so you really should just use the joins predicate: Foo.joins(:bar) Select * from Foo Inner Join Bars ... But, for the record, if you want a "NOT NULL" condition simply use the not predicate: Foo.includes(:bar).where.not(bars: {id: nil}) Select * from Foo Left Outer Join Bars on .. WHERE ...
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How do I dump the data of some SQLite3 tables?

...SOME_STRING' for something other than a comma. .headers on .out file.csv select * from MyTable; If you want to reinsert into a different SQLite database then: .mode insert <target_table_name> .out file.sql select * from MyTable; ...