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What does string::npos mean in this code?
..."not found"); // assume it returns npos
if (idx == std::string::npos) { // ERROR: comparison might not work
...
}
One way to avoid this error is to check whether the search fails directly:
if (s.find("hi") == std::string::npos) {
...
}
However, often you need the index of the matching character...
Define css class in django Forms
...way :
<form action="/contact/" method="post">
{{ form.non_field_errors }}
<div class="fieldWrapper">
{{ form.subject.errors }}
<label for="id_subject">Email subject:</label>
{{ form.subject }}
</div>
</form>
form.subject is a...
Detect IF hovering over element with jQuery
...as trying to check multiple elements at a time. This was throwing Uncaught Error: Syntax error, unrecognized expression: unsupported pseudo: hover.
So, working with his fiddle, this does NOT work:
var isHovered = !!$('#up, #down').filter(":hover").length;
While this DOES work:
var isHovered = !...
How to find out which processes are using swap space in Linux?
..."" ] && { SORT="$1"; }
[ ! -x `which mktemp` ] && { echo "ERROR: mktemp is not available!"; exit; }
MKTEMP=`which mktemp`;
TMP=`${MKTEMP} -d`;
[ ! -d "${TMP}" ] && { echo "ERROR: unable to create temp dir!"; exit; }
>${TMP}/${SCRIPT_NAME}.pid;
>${TMP}/${SCRIPT_NAME}.k...
C++ catch blocks - catch exception by value or reference? [duplicate]
...yException which inherits from CustomException and overrides items like an error code. If a MyException type was thrown your catch block would cause it to be converted to a CustomException instance which would cause the error code to change.
...
How to compare variables to undefined, if I don’t know whether they exist? [duplicate]
...ere.
}
Note that typeof always returns a string, and doesn't generate an error if the variable doesn't exist at all.
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What is aspect-oriented programming?
...llow Single Responsiblity by moving these cross-cutting concerns (logging, error handling, etc.) out of the main components of your application. When used appropriately AOP can lead to higher levels of maintainability and extensibility in your application over time.
...
Never seen before C++ for loop
I was converting a C++ algorithm to C#.
I came across this for loop:
12 Answers
12
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Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
...than the x87) makes a reasonable attempt at following IEEE 754 - it's not "error bounds"; there is only one correct answer.
– tc.
Jun 22 '11 at 2:19
14
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Apache shows PHP code instead of executing it
...member the extension but I think it's .so.
Also check in /var/log/apache2/error.log to see if you have any other errors.
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