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Case objects vs Enumerations in Scala
...
One big difference is that Enumerations come with support for instantiating them from some name String. For example:
object Currency extends Enumeration {
val GBP = Value("GBP")
val EUR = Value("EUR") //etc.
}
Then yo...
Why does Java's hashCode() in String use 31 as a multiplier?
...iplying by 31 can be relatively cheap. On an ARM, for instance, it is only one instruction:
RSB r1, r0, r0, ASL #5 ; r1 := - r0 + (r0<<5)
Most other processors would require a separate shift and subtract instruction. However, if your multiplier is slow this is still a win. Modern p...
Class JavaLaunchHelper is implemented in both … libinstrument.dylib. One of the two will be used. Wh
...of my app. I'm still getting the same issue with the version you have mentioned above. though I've tried many 8 version with its patches in my mac os. No Luck.
– Sathish
May 10 '17 at 8:20
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Twitter oAuth callbackUrl - localhost development
Is anyone else having a difficult time getting Twitters oAuth's callback URL to hit their localhost development environment.
Apparently it has been disabled recently. http://code.google.com/p/twitter-api/issues/detail?id=534#c1
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Was PreferenceFragment intentionally excluded from the compatibility package?
...rection is to use PreferenceFragment on Android 3.0 and higher.
Can anyone tell me whether this was intentional?
My guess is it's a question of engineering time, but that's just a guess.
If so, can I easily target a range of devices (i.e. < 3.0 and >=3.0) or will I have to jump thr...
Why an abstract class implementing an interface can miss the declaration/implementation of one of th
... it makes better sense to factor it into a separate base class (DRY trumps one-place-code)
– Gishu
Oct 13 '08 at 15:23
4
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SQL: deleting tables with prefix
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I have only one database so i wont need the 2nd one.
– Deniz Zoeteman
Oct 19 '09 at 15:38
4
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Group by multiple columns in dplyr, using string vector input
...= names(data)[-3]
library(dplyr)
df1 <- data %>%
group_by_at(vars(one_of(columns))) %>%
summarize(Value = mean(value))
#compare plyr for reference
df2 <- plyr::ddply(data, columns, plyr::summarize, value=mean(value))
table(df1 == df2, useNA = 'ifany')
## TRUE
## 27
The output ...
How does one make random number between range for arc4random_uniform()?
...al extension of either Int or Range. I would simply add this as a stand-alone function in a utilities file.
– Vince O'Sullivan
Nov 16 '15 at 9:31
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Git stash: “Cannot apply to a dirty working tree, please stage your changes”
... have to apply stashed changes to a dirty working copy, e.g. pop more than one changeset from the stash, I use the following:
$ git stash show -p | git apply -3 && git stash drop
Basically it
creates a patch
pipes that to the apply command
if there are any conflicts they will need to b...