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Good reasons to prohibit inheritance in Java?
...o be extended, and with enough documentation to describe how it should be done
Classes marked final
If you are writing purely internal code this may be a bit of overkill. However the extra effort involved in adding five characters to a class file is very small. If you are writing only for internal...
Use of alloc init instead of new
...ttp://macresearch.org/difference-between-alloc-init-and-new
Some selected ones are:
new doesn't support custom initializers (like initWithString)
alloc-init is more explicit than new
General opinion seems to be that you should use whatever you're comfortable with.
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Is onload equal to readyState==4 in XMLHttpRequest?
...al clear separation between XHR 1 and XHR 2 anymore, they have merged into one standard. The most common feature that represents XHR 2 is CORS support so from that standpoint XHR 2 didn't appear in IE until IE 10 but XHR.onload was supported in IE 9 which is typically believed to be XHR 1.
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How big is too big for a PostgreSQL table?
...uch data will exist, test it for your volume and see what you get. Testing one table with 90 million rows may be as easy as:
select x,1 as c2,2 as c3
from generate_series(1,90000000) x;
https://wiki.postgresql.org/wiki/FAQ
Limit Value
Maximum Database Size Unlimited
Maximum Table Size ...
Structs versus classes
I'm about to create 100,000 objects in code. They are small ones, only with 2 or 3 properties. I'll put them in a generic list and when they are, I'll loop them and check value a and maybe update value b .
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How does Facebook Sharer select Images and other metadata when sharing my URL?
...raph meta tags that it looks at to decide which image to show.
The keys one for the Facebook image are:
<meta property="og:image" content="http://ia.media-imdb.com/rock.jpg"/>
<meta property="og:image:secure_url" content="https://secure.example.com/ogp.jpg" />
and it should be pr...
What is the proper way to check if a string is empty in Perl?
...
As already mentioned by several people, eq is the right operator here.
If you use warnings; in your script, you'll get warnings about this (and many other useful things); I'd recommend use strict; as well.
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Scatterplot with marginal histograms in ggplot2
...vote than the correct answer. My understanding is that this is essentially one-dimensional heatmap: the rugs are darker wherever is crowded. My only worry would be, heatmap's resolution is not as high as a histogram. e.g.. when the plot is small, all rugs will be squeezed together, which makes it ha...
Checking in of “commented out” code [closed]
...ow you'd enforce that anyway). What I will say is that you should get everyone on your team to buy in to the philosophy I described above. The team I work on embraces it wholeheartedly. As a result, source control is a frictonless team-member, one that helps us get our job done.
People who don't em...
How to work around the lack of transactions in MongoDB?
...e only worked with SQL databases so far), or whether it actually can't be done.
10 Answers
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