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Appending an element to the end of a list in Scala
...'s because you shouldn't do it (at least with an immutable list).
If you really really need to append an element to the end of a data structure and this data structure really really needs to be a list and this list really really has to be immutable then do eiher this:
(4 :: List(1,2,3).reverse).rev...
What is the use for Task.FromResult in C#
In C# and TPL ( Task Parallel Library ), the Task class represents an ongoing work that produces a value of type T.
6 Ans...
Why is char[] preferred over String for passwords?
... believe this is implementation-specific - the garbage collector may clear all memory as it goes, to avoid this sort of thing. Even if it does, there's still the time during which the char[] contains the actual characters as an attack window.
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Why does `a == b or c or d` always evaluate to True?
...r is more literal minded.
if name == "Kevin" or "Jon" or "Inbar":
is logically equivalent to:
if (name == "Kevin") or ("Jon") or ("Inbar"):
Which, for user Bob, is equivalent to:
if (False) or ("Jon") or ("Inbar"):
The or operator chooses the first argument with a positive truth value:
if ("Jon")...
What's the difference between identifying and non-identifying relationships?
...t make the foreign key to the parent part of the child's primary key. Formally, the "right" way to do this is to make the foreign key part of the child's primary key. But the logical relationship is that the child cannot exist without the parent.
Example: A Person has one or more phone numbers. ...
Determine the type of an object?
...object, and isinstance() to check an object’s type against something. Usually, you want to use isistance() most of the times since it is very robust and also supports type inheritance.
To get the actual type of an object, you use the built-in type() function. Passing an object as the only param...
Enabling auto layout in iOS 6 while remaining backwards compatible with iOS 5
...ve of your .app file. Does having two targets make that process harder at all? Thanks.
– Crystal
May 16 '13 at 2:55
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Getting the last element of a list
...ist[-1] gets the last element, some_list[-2] gets the second to last, etc, all the way down to some_list[-len(some_list)], which gives you the first element.
You can also set list elements in this way. For instance:
>>> some_list = [1, 2, 3]
>>> some_list[-1] = 5 # Set the last e...
.rar, .zip files MIME Type
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actually there's another MIME TYPE for zip, and that's: application/x-zip-compressed
– Kiyarash
Oct 6 '14 at 19:21
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Django - what is the difference between render(), render_to_response() and direct_to_template()?
...and spanking new shortcut for render_to_response in 1.3 that will automatically use RequestContext that I will most definitely be using from now on.
2020 EDIT: It should be noted that render_to_response() was removed in Django 3.0
https://docs.djangoproject.com/en/1.8/topics/http/shortcuts/#rend...