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What is the difference between a map and a dictionary?
...cond set (the range).
As such, a map data structure provides a way to go from elements of a given set - known as "keys" in the map, to one or more elements in the second set - known as the associated "value(s)".
The "...or more elements in the second set" aspect can be supported by an implementati...
How to tell when UITableView has completed ReloadData?
...: and tableView:numberOfRowsInSection: to its data source before returning from reloadData. If the delegate implements tableView:heightForRowAtIndexPath:, the table view also sends that (for each row) before returning from reloadData.
However, the table view does not send tableView:cellForRowAtInd...
Rails: How do I create a default value for attributes in Rails activerecord's model? [duplicate]
...s after the Ruby initialize. Hence it is run every time a record is loaded from the database and used to create a new model object in memory, so don't use this callback if what you want is just to set default values the first time you add a new record. If you want to do that, use before_create and n...
jQuery Scroll to bottom of page/iframe
...
scrollTop() returns the number of pixels that are hidden from view from the scrollable area, so giving it:
$(document).height()
will actually overshoot the bottom of the page. For the scroll to actually 'stop' at the bottom of the page, the current height of the browser window n...
What is a user agent stylesheet?
...
@ChrisMorgan quoting from the specification to which you have linked: "DOCTYPEs are required for legacy reasons. When omitted, browsers tend to use a different rendering mode that is incompatible with some specifications. Including the DOCTYPE in...
Does it make sense to use “as” instead of a cast even if there is no null check? [closed]
... is+cast is enough to trigger a "Do not cast unnecessarily" warning from FxCop: msdn.microsoft.com/en-us/library/ms182271.aspx That should be enough reason to avoid the construct.
– David Schmitt
Jan 27 '10 at 16:47
...
how to check the jdk version used to compile a .class file [duplicate]
...ws:
javap -verbose MyClass | findstr "major"
You want the major version from the results. Here are some example values:
Java 1.2 uses major version 46
Java 1.3 uses major version 47
Java 1.4 uses major version 48
Java 5 uses major version 49
Java 6 uses major version 50
Java 7 uses major versio...
#pragma pack effect
...what the 8 byte boundary already gave you. You'll get the same performance from the CPU, while getting much worse cache utilization for the reasons outlined in that post.
– jalf
May 14 '15 at 18:30
...
String is immutable. What exactly is the meaning? [duplicate]
...ields (or the fields are public and not final, so that they can be updated from outside without accessing them via methods), for example:
Foo x = new Foo("the field");
x.setField("a new field");
System.out.println(x.getField()); // prints "a new field"
While in an immutable class (declared as fin...
Converting bool to text in C++
...ar * const BoolToString(bool b)
{
return b ? "true" : "false";
}
Aside from that I have a few other gripes, particularly with the accepted answer :)
// this is used in C, not C++. if you want to use printf, instead include <cstdio>
//#include <stdio.h>
// instead you should use the ...