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Why does Enumerable.All return true for an empty sequence? [duplicate]
...cate, or if the sequence is empty; otherwise, false.
Now you can argue about whether or not it should work that way (it seems fine to me; every element of the sequence conforms to the predicate) but the very first thing to check before you ask whether something is a bug, is the documentation. (It'...
Setting DIV width and height in JavaScript
...getElementById('div_register').style.width='500px';
I also want to point out that a much easier method of managing styles is to use a CSS class selector and put your styles in external CSS files. Not only will your code be much more maintainable, but you'll actually make friends with your Web desi...
How to avoid “if” chains?
...o there is no way you would want to join them into single if statement without screwing readability. And it is not always easy to move those conditions to outer functions, because they may be dependent on a lot of previously calculated local variables, which would create a terrible mess if you try t...
What's the nearest substitute for a function pointer in Java?
I have a method that's about ten lines of code. I want to create more methods that do exactly the same thing, except for a small calculation that's going to change one line of code. This is a perfect application for passing in a function pointer to replace that one line, but Java doesn't have func...
How much faster is C++ than C#?
...optimized programs, where expert programmers thoroughly optimized the hell out of the code. This is not only very time consuming (and thus expensive), but also commonly leads to errors due to over-optimizations.
On the other hand, code in interpreted languages gets faster in later versions of the r...
C++ multiline string literal
...nd, I've gone crazy \
and really let the literal span several lines, \
without bothering with quoting each line's \
content. This works, but you can't indent.";
Again, note those backslashes at the end of each line, they must be immediately before the line ends, they are escaping the newline in th...
String literals: Where do they go?
... segments so the data segment will be writable.
Rather then try to figure out a trick to make string literals changeable (it will be highly dependent on your platform and could change over time), just use arrays:
char foo[] = "...";
The compiler will arrange for the array to get initialized from...
Split delimited strings in a column and insert as new rows [duplicate]
...ip.white = TRUE)
require(data.table)
d.dt <- data.table(d.df, key="V1")
out <- d.dt[, list(V2 = unlist(strsplit(V2, ","))), by=V1]
# V1 V2
# 1: 1 a
# 2: 1 b
# 3: 1 c
# 4: 2 a
# 5: 2 c
# 6: 3 b
# 7: 3 d
# 8: 4 e
# 9: 4 f
> sapply(out$V2, nchar) # (or simply nchar(out$V...
How do you compare two version Strings in Java?
...o(minVersion) < 0 || version.compareTo(maxVersion) > 0) {
System.out.println("Sorry, your version is unsupported");
}
You can get the right dependency string for Maven Artifact from this page:
<dependency>
<groupId>org.apache.maven</groupId>
<artifactId>maven-art...
Use of undeclared identifier 'kUTTypeMovie'
...m a novice at iOS development and xcode and spent some time trying to find out why just the import was not working. After figuring out the problem with a more experienced member of my team I found out that not only must you include
#import <MobileCoreServices/MobileCoreServices.h>
but you m...