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Equivalent of .try() for a hash to avoid “undefined method” errors on nil? [duplicate]
...address)
can be rewritten to
account&.owner&.address
However, one should be careful that & is not a drop in replacement of #try. Take a look at this example:
> params = nil
nil
> params&.country
nil
> params = OpenStruct.new(country: "Australia")
#<OpenStruct countr...
Move branch pointer to different commit without checkout
To move the branch pointer of a checked out branch, one can use the git reset --hard command. But how to move the branch pointer of a not-checked out branch to point at a different commit (keeping all other stuff like tracked remote branch)?
...
WWW or not WWW, what to choose as primary site name? [closed]
From technical perspective the only issue is traffic and incoming links (one of them should redirect to another).
14 Answe...
Javascript calculate the day of the year (1 - 366)
...r start = new Date(now.getFullYear(), 0, 0);
var diff = now - start;
var oneDay = 1000 * 60 * 60 * 24;
var day = Math.floor(diff / oneDay);
console.log('Day of year: ' + day);
Edit: The code above will fail when now is a date in between march 26th and October 29th andnow's time is before ...
How is Node.js inherently faster when it still relies on Threads internally?
...ak due to bugs and 2) not use them as efficiently as possible. (2) is the one you're asking about.
Think about one of the examples he gives, where a request comes in and you run some query, and then do something with the results of that. If you write it in a standard procedural way, the code migh...
What and where are the stack and heap?
...f the stack; freeing a block from the stack is nothing more than adjusting one pointer.
The heap is memory set aside for dynamic allocation. Unlike the stack, there's no enforced pattern to the allocation and deallocation of blocks from the heap; you can allocate a block at any time and free it at...
Regex Pattern to Match, Excluding when… / Except between
...ontexts is a special challenge.
Surprise
Surprisingly, there is at least one efficient solution that is general, easy to implement and a pleasure to maintain. It works with all regex flavors that allow you to inspect capture groups in your code. And it happens to answer a number of common question...
Random number generator only generating one random number
...need to write ''two'' lines of code to generate a random number instead of one. Is this really worth it to save reading one simple line of code?
– EMP
Apr 15 '10 at 23:07
5
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Looping over arrays, printing both index and value
...e), so:
for i in "${!foo[@]}"; do
printf "%s\t%s\n" "$i" "${foo[$i]}"
done
Which means that indices will be in $i while the elements themselves have to be accessed via ${foo[$i]}
share
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impro...
MySQL Multiple Joins in one query?
...hich will return all your dashboard messages and an image_filename only if one exists (otherwise you'll get a null)
SELECT dashboard_data.headline, dashboard_data.message, dashboard_messages.image_id, images.filename
FROM dashboard_data
INNER JOIN dashboard_messages
ON dashboard_messa...