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How to map and remove nil values in Ruby
...s = [1, 2, 5, 8, 10, 13]
enum.filter_map { |i| i * 2 if i.even? }
# => [4, 16, 20]
In your case, as the block evaluates to falsey, simply:
items.filter_map { |x| process_x url }
"Ruby 2.7 adds Enumerable#filter_map" is a good read on the subject, with some performance benchmarks against some...
Default initialization of std::array?
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edited Aug 18 '13 at 5:24
answered Aug 18 '13 at 4:59
Cas...
Why {} + {} is NaN only on the client side? Why not in Node.js?
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Updated note: this has been fixed in Chrome 49.
Very interesting question! Let's dig in.
The root cause
The root of the difference is in how Node.js evaluates these statements vs. how the Chrome development tools do.
What Node.js does
Node.js uses the repl module ...
How to implement a binary tree?
...nt(str(node.v) + ' ')
self._printTree(node.r)
# 3
# 0 4
# 2 8
tree = Tree()
tree.add(3)
tree.add(4)
tree.add(0)
tree.add(8)
tree.add(2)
tree.printTree()
print(tree.find(3).v)
print(tree.find(10))
tree.deleteTree()
tree.printTree()
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Purpose of ESI & EDI registers?
...es into
8B550C mov edx,[ebp+0C]
8B0C9A mov ecx,[edx+4*ebx]
894CBDAC mov [ebp+4*edi-54],ecx
47 inc edi
where ebp+12 contains argv, ebx is j, and edi has srcidx. Notice the third instruction uses edi mulitplied by 4 and adds ebp offset by 0x54 (the lo...
Git: Correct way to change Active Branch in a bare repository?
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edited May 23 '17 at 11:54
Community♦
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answered Jul 21 '10 at 17:22
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Regex - how to match everything except a particular pattern
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Pro Backup
6451212 silver badges2929 bronze badges
answered Mar 4 '09 at 18:41
GumboGumbo
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Is there auto type inferring in Java?
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edited Jul 12 '13 at 4:26
answered Apr 21 '13 at 15:28
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What does the “map” method do in Ruby?
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432
The map method takes an enumerable object and a block, and runs the block for each element, ou...
Font Awesome not working, icons showing as squares
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