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Convert a String representation of a Dictionary to a dictionary?
...gt;>> import ast
>>> ast.literal_eval("{'muffin' : 'lolz', 'foo' : 'kitty'}")
{'muffin': 'lolz', 'foo': 'kitty'}
This is safer than using eval. As its own docs say:
>>> help(ast.literal_eval)
Help on function literal_eval in module ast:
literal_eval(node_or_string)
...
do { … } while (0) — what is it good for? [duplicate]
...ter, and still use within an if statement. An example might help:
#define FOO(x) foo(x); bar(x)
if (condition)
FOO(x);
else // syntax error here
...;
Even using braces doesn't help:
#define FOO(x) { foo(x); bar(x); }
Using this in an if statement would require that you omit the semico...
How do I create a constant in Python?
...ust don't change it.
If you are in a class, the equivalent would be:
class Foo(object):
CONST_NAME = "Name"
if not, it is just
CONST_NAME = "Name"
But you might want to have a look at the code snippet Constants in Python by Alex Martelli.
As of Python 3.8, there's a typing.Final variable anno...
What does principal end of an association means in 1:1 relationship in Entity framework
... so in your case you should use:
public class Boo
{
[Key, ForeignKey("Foo")]
public string BooId{get;set;}
public Foo Foo{get;set;}
}
Or fluent mapping
modelBuilder.Entity<Foo>()
.HasOptional(f => f.Boo)
.WithRequired(s => s.Foo);
...
Best way to give a variable a default value (simulate Perl ||, ||= )
I love doing this sort of thing in Perl: $foo = $bar || $baz to assign $baz to $foo if $bar is empty or undefined. You also have $foo ||= $bletch which will only assign $bletch to $foo if $foo is not defined or empty.
...
Ruby: Calling class method from instance
...s, inside an instance method you can just call self.class.whatever.
class Foo
def self.some_class_method
puts self
end
def some_instance_method
self.class.some_class_method
end
end
print "Class method: "
Foo.some_class_method
print "Instance method: "
Foo.new.some...
What does `someObject.new` do in Java?
...class it uses the this instance of the container by default:
public class Foo {
int val;
public Foo(int v) { val = v; }
class Bar {
public void printVal() {
// this is the val belonging to our containing instance
System.out.println(val);
}
}
public Bar createBar() {
...
How to select all instances of a variable and edit variable name in Sublime
...
its still selecting everything which has foo inside.
– user1767754
Jun 2 '15 at 1:35
1
...
C++ where to initialize static const
...
Anywhere in one compilation unit (usually a .cpp file) would do:
foo.h
class foo {
static const string s; // Can never be initialized here.
static const char* cs; // Same with C strings.
static const int i = 3; // Integral types can be initialized here (*)...
static const...
C# operator overload for `+=`?
...rogram in C#, and you can simply overload + operator.
For example:
class Foo
{
private int c1;
public Foo(int c11)
{
c1 = c11;
}
public static Foo operator +(Foo c1, Foo x)
{
return new Foo(c1.c1 + x.c1);
}
}
static void Main(string[] args)
{
Foo ...