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What is the difference between a var and val definition in Scala?
What is the difference between a var and val definition in Scala and why does the language need both? Why would you choose a val over a var and vice versa?
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How can I get the MAC and the IP address of a connected client in PHP?
I need to know the MAC and the IP address of the connect clients, how can I do this in PHP?
16 Answers
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Difference Between Schema / Database in MySQL
Is there a difference between a schema and a database in MySQL? In SQL Server, a database is a higher level container in relation to a schema.
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Showing all errors and warnings [duplicate]
...iguration option will keep this new value during the script's execution , and will be restored at the script's ending .
– jave.web
Dec 8 '14 at 22:04
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Thou shalt not inherit from std::vector
... the hell it is before using it. What's the difference between std::vector and MyVector? Which one is better to use here and there? What if I need to move std::vector to MyVector? May I just use swap() or not?
Do not produce new entities just to make something to look better. These entities (especi...
What is the difference between “expose” and “publish” in Docker?
I'm experimenting with Dockerfiles, and I think I understand most of the logic. However, I don't see the difference between "exposing" and "publishing" a port in this context.
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How to output only captured groups with sed?
...as well as specifying what you do want.
string='This is a sample 123 text and some 987 numbers'
echo "$string" | sed -rn 's/[^[:digit:]]*([[:digit:]]+)[^[:digit:]]+([[:digit:]]+)[^[:digit:]]*/\1 \2/p'
This says:
don't default to printing each line (-n)
exclude zero or more non-digits
include on...
When to call activity context OR application context?
...plicationContext() when you know why you are using getApplicationContext() and only when you need to use getApplicationContext().
To be blunt, "some programmers" use getApplicationContext() (or getBaseContext(), to a lesser extent) because their Java experience is limited. They implement an inner c...
Find location of a removable SD card
...le via USB Mass Storage mode when mounted on a host machine", at least for Android 1.x and 2.x.
But the question is about external SD. How to get a path like "/mnt/sdcard/external_sd" (it may differ from device to device)?
Android has no concept of "external SD", aside from external storage, as de...
When to use PNG or JPG in iPhone development?
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PNG's are pixel perfect (non-lossy), and require very little extra CPU energy to display. However, large PNGs may take longer to read from storage than more compressed image formats, and thus be slower to display.
JPG's are smaller to store, but lossy (amount ...