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How to decide font color in white or black depending on background color?
...e intensities. Each 2 digits of the code represent a value in hexadecimal (base-16) notation. I won't get into the details of the conversion here, they're easy to look up.
Once you have the intensities for the individual colors, you can determine the overall intensity of the color and choose the co...
delegate keyword vs. lambda notation
...hing trick)...
using System;
using System.Linq.Expressions;
public class Base
{
public void Foo(Action action)
{
Console.WriteLine("I suspect the lambda expression...");
}
}
public class Derived : Base
{
public void Foo(Action<int> action)
{
Console.Write...
How to convert numbers between hexadecimal and decimal
... @ColeJohnson int.Parse doesn't have an option for you to specify the base as an int, just as one of a few valid NumberStyles. For base 16, either is just fine, but as a general solution, it's good to know how both work.
– Tim S.
Oct 21 '13 at 20:44
...
Font size in CSS - % or em?
...mpletely avoids certain really annoying browser quirks when it comes to em-based line-heights
– Már Örlygsson
Oct 29 '08 at 3:39
17
...
What is the difference between conversion specifiers %i and %d in formatted IO functions (*printf /
...haracters.
On the other hand for scanf there is a difference, %d assume base 10 while %i auto detects the base. We can see this by going to section 7.19.6.2 The fscanf function which covers scanf with respect to format specifier, in paragraph 12 it says:
The conversion specifiers and their me...
Clang optimization levels
...asses is available here.
With version 6.0 the passes are as follow:
baseline (-O0):
opt sets: -tti -verify -ee-instrument -targetlibinfo -assumption-cache-tracker -profile-summary-info -forceattrs -basiccg -always-inline -barrier
clang adds : -mdisable-fp-elim -mrelax-all
-O1 is based on -...
When should static_cast, dynamic_cast, const_cast and reinterpret_cast be used?
...inheritance hierarchies. It is unnecessary when casting upwards (towards a base class), but when casting downwards it can be used as long as it doesn't cast through virtual inheritance. It does not do checking, however, and it is undefined behavior to static_cast down a hierarchy to a type that isn'...
SQLAlchemy - Getting a list of tables
... the metadata yourself. Fortunately, the metadata is still present on 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 have...
Generating a SHA-256 hash from the Linux command line
...
For the sha256 hash in base64, use:
echo -n foo | openssl dgst -binary -sha1 | openssl base64
Example
echo -n foo | openssl dgst -binary -sha1 | openssl base64
C+7Hteo/D9vJXQ3UfzxbwnXaijM=
...
Get properties and values from unknown object
...e members to a file, but you shouldn't use this information to drive logic based on property sets.
Assuming you have control over the implementations of the types, you should derive from a common base class or implement a common interface and make the calls on those (you can use the as or is operat...