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dynamic_cast and static_cast in C++
...t runtime, and work by querying the object (no need to worry about how for now), asking it if it the type we're looking for. If it is, dynamic_cast<Type*> returns a pointer; otherwise it returns NULL.
In order for this base-to-derived casting to work using dynamic_cast<>, Base, Foo and...
Rails.env vs RAILS_ENV
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ENV['RAILS_ENV'] is now deprecated.
You should use Rails.env which is clearly much nicer.
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Mysql: Select rows from a table that are not in another
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If you have 300 columns as you mentioned in another comment, and you want to compare on all columns (assuming the columns are all the same name), you can use a NATURAL LEFT JOIN to implicitly join on all matching column names...
Adding minutes to date time in PHP
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With date: 2011-11-18 00:00 if I add 5 mins, I get 2012-04-18 00:00 as a result. ` $time = new DateTime($_REQUEST['start']); $time->add(new DateInterval('P' . $duration . 'M')); $endTime = $time->format('Y-m-d H:i'); echo $endTime; ` Applogies f...
Pimpl idiom vs Pure virtual class interface
...s case, because it's the only member) from the pointer to the A object it knows to be this.
On the user side of the code, a new A will first allocate sizeof(A) bytes of memory, then hand a pointer to that memory to the A::A() constructor as this.
If in a later revision of your library you decide t...
read.csv warning 'EOF within quoted string' prevents complete reading of file
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Thanks, that's an easy fix. Now what do you think about getting fread working in this situation? I prefer that because it's a lot faster than read.csv. But fread doesn't seem to take a quote argument..
– Ben
Jul 1 ...
How can I change a file's encoding with vim?
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all our base encoding are now belong to UTF-8
– roblogic
Aug 25 '15 at 1:49
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What does the @ symbol before a variable name mean in C#? [duplicate]
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With what is it any different than, say, an underscore?
– Vilx-
Jan 9 '09 at 20:15
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Remove excess whitespace from within a string
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Not sure exactly what you want but here are two situations:
If you are just dealing with excess whitespace on the beginning or end of the string you can use trim(), ltrim() or rtrim() to remove it.
If you are dealing with extra spaces within a string consider a preg_replace of multipl...
What does the filter parameter to createScaledBitmap do?
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Also, do you know if it's doing area averaging if you pass filter = true?
– clahey
Nov 5 '10 at 15:36
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