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C/C++ include header file order
...our method can introduce hidden dependencies, say if myclass.cpp includes <string> then <myclass.h>, there's no way to catch at build time that myclass.h may itself depend on string; so if later on you, or someone else, includes myclass.h but don't need string, you'll get an error that n...
Matching an empty input box using CSS
...d
#foo-thing:valid + .msg { visibility: visible!important; }
<input type="text" id="foo-thing" required="required">
<span class="msg" style="visibility: hidden;">Yay not empty</span>
See live on jsFiddle
OR negate using #foo-thing:invalid (credit to @SamGoody...
R - Concatenate two dataframes?
...
You want "rbind".
b$b <- NA
new <- rbind(a, b)
rbind requires the data frames to have the same columns.
The first line adds column b to data frame b.
Results
> a <- data.frame(a=c(0,1,2), b=c(3,4,5), c=c(6,7,8))
> a
a b c
1 0 ...
How can I remove all objects but one from the workspace in R?
...e. Run this at your own risk - it will remove all variables except x:
x <- 1
y <- 2
z <- 3
ls()
[1] "x" "y" "z"
rm(list=setdiff(ls(), "x"))
ls()
[1] "x"
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Convert String to Type in C# [duplicate]
...oo. See the documentation for Type.GetType(string) for more information.
Alternatively, if you have a reference to the assembly already (e.g. through a well-known type) you can use Assembly.GetType:
Assembly asm = typeof(SomeKnownType).Assembly;
Type type = asm.GetType(namespaceQualifiedTypeName);...
Spring JPA selecting specific columns
... projects";
@Query(value = FIND_PROJECTS, nativeQuery = true)
public List<Object[]> findProjects();
Note that you will have to do the mapping yourself though. It's probably easier to just use the regular mapped lookup like this unless you really only need those two values:
public List<P...
Repeat Character N Times
In Perl I can repeat a character multiple times using the syntax:
23 Answers
23
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Apache2: 'AH01630: client denied by server configuration'
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In my case I have error in DocumentRoot and <Directory> paths.
– Roman Grinyov
Jan 3 '17 at 20:19
4
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How can I return an empty IEnumerable?
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You can use list ?? Enumerable.Empty<Friend>(), or have FindFriends return Enumerable.Empty<Friend>()
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How to return an array from JNI to Java?
...ArrayTest_initIntArray(JNIEnv *env, jclass cls, int size)
{
jintArray result;
result = (*env)->NewIntArray(env, size);
if (result == NULL) {
return NULL; /* out of memory error thrown */
}
int i;
// fill a temp structure to use to populate the java int array
jint fill[size];
for (i =...