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How to map and remove nil values in Ruby
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Ruby 2.7 is introducing filter_map for this exact purpose. It's idiomatic and performant, and I'd expect it to become the norm very soon.
For example:
numbers = [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, simp...
Why is the gets function so dangerous that it should not be used?
...hat.)
It remained an official part of the language up to the 1999 ISO C standard, but
it was officially removed by the 2011 standard. Most C implementations still support it, but at least gcc issues a warning for any code that uses it.
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Maintain aspect ratio of div but fill screen width and height in CSS?
...ite to put together that has a fixed aspect ratio of approximately 16:9 landscape, like a video.
9 Answers
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Most efficient method to groupby on an array of objects
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Here is one that outputs array and not object: groupByArray(xs, key) { return xs.reduce(function (rv, x) { let v = key instanceof Function ? key(x) : x[key]; let el = rv.find((r) => r && r.key === v); ...
Red black tree over avl tree
AVL and Red black trees are both self-balancing except Red and black color in the nodes. What's the main reason for choosing Red black trees instead of AVL trees? What are the applications of Red black trees?
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Search for one value in any column of any table inside a database
...s Kondreddi
-- Site: http://vyaskn.tripod.com
-- Tested on: SQL Server 7.0 and SQL Server 2000
-- Date modified: 28th July 2002 22:50 GMT
CREATE TABLE #Results (ColumnName nvarchar(370), ColumnValue nvarchar(3630))
SET NOCOUNT ON
DECLARE @TableName nvarchar(256), @ColumnName nvarchar(128), @Sear...
Catching error codes in a shell pipe
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If you really don't want the second command to proceed until the first is known to be successful, then you probably need to use temporary files. The simple version of that is:
tmp=${TMPDIR:-/tmp}/mine.$$
if ./a > $tmp.1
then
if ./b <$tmp.1 >$tmp.2
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How to Create Multiple Where Clause Query Using Laravel Eloquent?
I'm using the Laravel Eloquent query builder and I have a query where I want a WHERE clause on multiple conditions. It works, but it's not elegant.
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Print a list in reverse order with range()?
... may be less intuitive but as the comments mention, this is more efficient and the right usage of range for reversed list.
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How to change column datatype in SQL database without losing data
I have SQL Server database and I just realized that I can change the type of one of the columns from int to bool .
11 A...