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How to properly check if std::function is empty in C++11?
I was wondering how to properly check if an std::function is empty. Consider this example:
3 Answers
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Finding local IP addresses using Python's stdlib
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This appears to only return a single IP address. What if the machine has multiple addresses?
– Jason R. Coombs
Oct 23 '09 at 14:39
29
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Change Active Menu Item on Page Scroll?
... menuItems.map(function(){
var item = $($(this).attr("href"));
if (item.length) { return item; }
});
// Bind to scroll
$(window).scroll(function(){
// Get container scroll position
var fromTop = $(this).scrollTop()+topMenuHeight;
// Get id of current scroll item
var cur...
A non-blocking read on a subprocess.PIPE in Python
...standard output. Is there a way to make .readline non-blocking or to check if there is data on the stream before I invoke .readline ? I'd like this to be portable or at least work under Windows and Linux.
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How to check if BigDecimal variable == 0 in java?
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Use compareTo(BigDecimal.ZERO) instead of equals():
if (price.compareTo(BigDecimal.ZERO) == 0) // see below
Comparing with the BigDecimal constant BigDecimal.ZERO avoids having to construct a new BigDecimal(0) every execution.
FYI, BigDecimal also has constants BigDecimal.O...
How do I measure execution time of a command on the Windows command line?
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If you are using Windows 2003 (note that windows server 2008 and later are not supported) you can use The Windows Server 2003 Resource Kit, which contains timeit.exe that displays detailed execution stats. Here is an example...
Is it faster to count down than it is to count up?
...me reason it is more efficient to count down than to count up.
For example if you need to use a FOR loop and the loop index is not used somewhere (like printing a line of N * to the screen)
I mean that code like this:
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Android Preferences: How to load the default values when the user hasn't used the preferences-screen
...he readAgain argument to false means this will only set the default values if this method has never been called in the past so you don't need to worry about overriding the user's settings each time your Activity is created
Take a look into PreferenceManager.setDefaultValues in Android API for furthe...
Best way to include CSS? Why use @import?
... can prevent stylesheets from being downloaded concurrently. For instance, if stylesheet A contains the text:
@import url("stylesheetB.css");
then the download of the second stylesheet may not start until the first stylesheet has been downloaded. If, on the other hand, both stylesheets are refere...
How to insert text into the textarea at the current cursor position?
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function insertAtCursor(myField, myValue) {
//IE support
if (document.selection) {
myField.focus();
sel = document.selection.createRange();
sel.text = myValue;
}
//MOZILLA and others
else if (myField.selectionStart || myField.selectionStart == '0...