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How do you represent a graph in Haskell?
It's easy enough to represent a tree or list in haskell using algebraic data types. But how would you go about typographically representing a graph? It seems that you need to have pointers. I'm guessing you could have something like
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“Invalid form control” only in Google Chrome
...below works well in Safari but in Chrome and Firefox the form will not submit. Chrome console logs the error An invalid form control with name='' is not focusable . Any ideas?
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Multiline strings in JSON
I'm writing some data files in JSON format and would like to have some really long string values split over multiple lines. Using python's JSON module I get a whole lot of errors, whether I use \ or \n as an escape.
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Dynamically adding a form to a Django formset with Ajax
... a Django formset using Ajax, so that when the user clicks an "add" button it runs JavaScript that adds a new form (which is part of the formset) to the page.
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Declaring pointers; asterisk on the left or right of the space between the type and name? [duplicate
...ointers in one of two ways, and I have no idea which one is correct, of if it even matters.
6 Answers
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How to find the sum of an array of numbers
Given an array [1, 2, 3, 4] , how can I find the sum of its elements? (In this case, the sum would be 10 .)
43 Answers
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Why does Apple recommend to use dispatch_once for implementing the singleton pattern under ARC?
... (sharedInstance == nil) {
sharedInstance = [[MyClass alloc] init];
}
}
return sharedInstance;
}
The benefit of dispatch_once() over this is that it's faster. It's also semantically cleaner, because it also protects you from multiple threads doing alloc init of your sha...
Style input element to fill remaining width of its container
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as much as everyone hates tables for layout, they do help with stuff like this, either using explicit table tags or using display:table-cell
<div style="width:300px; display:table">
<label for="MyInput" style="display:table-cell; width:1px">label&nbsp;text</la...
Why can't I have abstract static methods in C#?
I've been working with providers a fair bit lately, and I came across an interesting situation where I wanted to have an abstract class that had an abstract static method. I read a few posts on the topic, and it sort of made sense, but is there a nice clear explanation?
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Is there a way to avoid null check before the for-each loop iteration starts? [duplicate]
Every time I have to iterate over a collection I end up checking for null, just before the iteration of the for-each loop starts. Like this:
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