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Why is using the JavaScript eval function a bad idea?
The eval function is a powerful and easy way to dynamically generate code, so what are the caveats?
26 Answers
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Should I Stop Stopwatch at the end of the method?
...so a Stopwatch isn't doing any work or eating cpu clock cycles between the calls to Start() and Stop(). Start() just sets a timestamp to now and Stop() calculates and saves the time elapsed since that. See source in coreclr: github.com/dotnet/corefx/blob/master/src/…
– Sammi...
Is Python strongly typed?
...
Python is strongly, dynamically typed.
Strong typing means that the type of a value doesn't change in unexpected ways. A string containing only digits doesn't magically become a number, as may happen in Perl. Every change of type requires an explici...
Overlaying histograms with ggplot2 in R
...are visible through each other. So you probably want to use three separate calls to geom_histogram, where each one gets it's own data frame and fill:
ggplot(histogram, aes(f0)) +
geom_histogram(data = lowf0, fill = "red", alpha = 0.2) +
geom_histogram(data = mediumf0, fill = "blue", alpha...
Set initial focus in an Android application
In my Android application it automatically focuses the first Button I have in my layout, giving it an orange outline. How can I set the initial focus preferably in XML, and can this be set to nothing?
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error: writable atomic property cannot pair a synthesized setter/getter with a user defined setter/g
...to supply more information on this question:
You can supply the @property call with your own method by writing
@property(setter = MySetterMethod:, getter = MyGetterMethod)
Notice the colon for the supplied setter method.
Reference Apple documentation
EDIT:
I'm not quite sure how the new ch...
R - Markdown avoiding package loading messages
...ify the R code itself instead of the chunk options, by wrapping the source call in suppressPackageStartupMessages(), suppressMessages(), and/or suppressWarnings(). E.g:
```{r echo=FALSE}
suppressWarnings(suppressMessages(suppressPackageStartupMessages({
source("C:/Rscripts/source.R")
})
```
You c...
Proper Linq where clauses
...e just written about this...
They're different in terms of what will be called - the first is equivalent to:
Collection.Where(x => x.Age == 10)
.Where(x => x.Name == "Fido")
.Where(x => x.Fat == true)
wheras the latter is equivalent to:
Collection.Where(x => x....
PHP function to generate v4 UUID
...e PHP docs explicitly caution that mt_rand() does not generate cryptographically secure values. In other words, values generated by this function may be predictable. If you need to ensure that the UUIDs are not predictable, you should rather use Jack's solution below, which makes use of the openssl_...
Reimport a module in python while interactive
...If a module imports objects from another module using from ... import ..., calling reload() for the other module does not redefine the objects imported from it — one way around this is to re-execute the from statement, another is to use import and qualified names (module.*name*) instead.
If a modu...