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What does && mean in void *p = &&abc;
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@Lundin: Same can be said of most compilers. __forceinline? __declspec(naked)? One of my favourite MSVCisms is: template<typename T> class X { friend T; }, which is invalid C++03.
– Sebastian Mach
Aug 17 '12 at 8:20
...
How to check if a value exists in a dictionary (python)
...ed for lookup operations:
>>> type(d.viewvalues())
<type 'dict_values'>
>>> type(d.values())
<type 'list'>
>>> type(d.itervalues())
<type 'dictionary-valueiterator'>
EDIT2: As per request in comments...
>>> T(lambda : 'four' in d.itervalues()...
Can't access object property, even though it shows up in a console log
...cess, but on the very next line of code, I can't access it with config.col_id_3 (see the "undefined" in the screenshot?). Can anyone explain this? I can get access to every other property except field_id_4 as well.
...
SQLAlchemy - Getting a list of tables
...the baseclass,
>>> Base = sqlalchemy.ext.declarative.declarative_base()
>>> Base.metadata
MetaData(None)
If you are trying to figure out what tables are present in your database, even among the ones you haven't even told SQLAlchemy about yet, then you can use table reflection. ...
Null coalescing in powershell
...ms -ne $null
[string]::Join(', ', ($instances | ForEach-Object -Process { $_.GetType() }))
# Result:
System.String, System.Int32, System.Int32, System.String, System.Object[],
System.Boolean, System.Boolean
-eq works similarly, which is useful for counting null entries:
($null, 'a', $null -eq $n...
ActiveModel::ForbiddenAttributesError when creating new user
...ntroller < ApplicationController
def create
@user = User.new(user_params)
# ...
end
private
def user_params
params.require(:user).permit(:username, :email, :password, :salt, :encrypted_password)
end
end
...
Iterate a list as pair (current, next) in Python
...
Since the_list[1:] actually creates a copy of the whole list (excluding its first element), and zip() creates a list of tuples immediately when called, in total three copies of your list are created. If your list is very large, you ...
Android: View.setID(int id) programmatically - how to avoid ID conflicts?
...same id number in the same hierarchy, then a call to findViewById([repeated_id]) would return the first view set with that one repeated id. That's what I meant.
– kaneda
Jun 19 '13 at 23:33
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What is the single most influential book every programmer should read? [closed]
... For Computer Scientists http://ecx.images-amazon.com/images/I/51HCJ5R42KL._SL500_BO2,204,203,200_AA219_PIsitb-sticker-dp-arrow,TopRight,-24,-23_SH20_OU02_.jpg
Discrete Mathematics For Computer Scientists by J.K. Truss.
While this doesn't teach you programming, it teaches you fundamental mathemati...
Toggle button using two image on different state
...
<ToggleButton
android:id="@+id/toggle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/check" <!--check.xml-->
android:layout_margin="10dp"
android:textOn=""
android:textOff="...