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What are metaclasses in Python?
... bits and pieces:
def make_hook(f):
"""Decorator to turn 'foo' method into '__foo__'"""
f.is_hook = 1
return f
class MyType(type):
def __new__(mcls, name, bases, attrs):
if name.startswith('None'):
return None
# Go over attributes and see if they shoul...
Static Classes In Java
... []args){
MyStaticClass.setMyStaticMember(5);
System.out.println("Static value: " + MyStaticClass.getMyStaticMember());
System.out.println("Value squared: " + MyStaticClass.squareMyStaticMember());
// MyStaticClass x = new MyStaticClass(); // results in compile time e...
MySQL: Can't create table (errno: 150)
...
From the MySQL - FOREIGN KEY Constraints Documentation:
If you re-create a table that was dropped, it must have a definition that conforms to the foreign key constraints referencing it. It must have the correct column names and types, and it must have index...
Truncate (not round) decimal places in SQL Server
...eric_expression is to be rounded. length must be an expression of type tinyint, smallint, or int. When length is a positive number, numeric_expression is rounded to the number of decimal positions specified by length. When length is a negative number, numeric_expression is rounded on the left side o...
How to get the current loop index when using Iterator?
...tor iter = list.listIterator();
while (iter.hasNext()) {
System.out.println("index: " + iter.nextIndex() + " value: " + iter.next());
}
Make sure you call the nextIndex BEFORE you actually get the next().
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How do I use prepared statements in SQlite in Android?
....getWritableDatabase();
SQLiteStatement stmt = db.compileStatement("INSERT INTO Country (code) VALUES (?)");
stmt.bindString(1, "US");
stmt.executeInsert();
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In Postgresql, force unique on combination of two columns
...
CREATE TABLE someTable (
id serial primary key,
col1 int NOT NULL,
col2 int NOT NULL,
unique (col1, col2)
)
autoincrement is not postgresql. You want a serial.
If col1 and col2 make a unique and can't be null then they make a good primary key:
CREATE TABLE someTable...
Why does the C# compiler not fault code where a static method calls an instance method?
...
UPDATE: Below answer was written in 2012, before the introduction of C# 7.3 (May 2018). In What's new in C# 7.3, the section Improved overload candidates, item 1, it is explained how the overload resolution rules have changed so that non-static overloads are discarded early. So...
Android ClickableSpan not calling onClick
...ng.sign_up_terms);
Spannable spannable = new SpannableString(stringTerms);
int indexTermsStart = stringTerms.indexOf("Terms");
int indexTermsEnd = indexTermsStart + 18;
spannable.setSpan(new UnderlineSpan(), indexTermsStart, indexTermsEnd, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
spannable.setSpan(new For...
Using printf with a non-null terminated string
...ich is NOT null terminated and you know its exact size, so how can you print that string with printf in C? I recall such a method but I can not find out now...
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