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What is an “unwrapped value” in Swift?
I'm learning Swift for iOS 8 / OSX 10.10 by following this tutorial , and the term " unwrapped value " is used several times, as in this paragraph (under Objects and Class ):
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What is wrong with using goto? [duplicate]
I was ramdomming through xkcd and saw this one (if also read some negative texts about them some years ago):
What is actually wrong with it? Why are goto's even possible in C++ then?
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MySQL Great Circle Distance (Haversine formula)
I've got a working PHP script that gets Longitude and Latitude values and then inputs them into a MySQL query. I'd like to make it solely MySQL. Here's my current PHP Code:
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What do people find difficult about C pointers? [closed]
...ve some pretty fundemental issues when getting their heads around pointers and pointer arithmetic.
29 Answers
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How to get the current date and time
How do I get the current date and time in Java?
10 Answers
10
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Is it safe to check floating point values for equality to 0?
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It is safe to expect that the comparison will return true if and only if the double variable has a value of exactly 0.0 (which in your original code snippet is, of course, the case). This is consistent with the semantics of the == operator. a == b means "a is equal to b".
It is not sa...
What are the differences between “generic” types in C++ and Java?
Java has generics and C++ provides a very strong programming model with template s.
So then, what is the difference between C++ and Java generics?
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Can you help me understand this? “Common REST Mistakes: Sessions are irrelevant”
Disclaimer: I'm new to the REST school of thought, and I'm trying to wrap my mind around it.
6 Answers
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Conditional formatting based on another cell's value
...low, it actually means "B{current_row}", so for C5 it's B5, for C6 it's B6 and so on. Unless you specify $B$5 - then you refer to one specific cell.
This is supported in Google Sheets as of 2015:
https://support.google.com/drive/answer/78413#formulas
In your case, you will need to set conditiona...
How many database indexes is too many?
...nds on the operations that occur on the table.
If there's lots of SELECTs and very few changes, index all you like.... these will (potentially) speed the SELECT statements up.
If the table is heavily hit by UPDATEs, INSERTs + DELETEs ... these will be very slow with lots of indexes since they all ...