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Differences in boolean operators: & vs && and | vs ||
...ou're talking about the logical meaning of both operators, here you have a table-resume:
boolean a, b;
Operation Meaning Note
--------- ------- ----
a && b logical AND short-circuiting
a || b logical OR ...
What does && mean in void *p = &&abc;
... that address points to a instruction within the .text section of the executable. The .text section is the one which holds you program's (binary) code to be executed.
You can inspect this with:
objdump -x a.out
A practical example
As described in GCC, you can use this to initialize a jump table. S...
How to write a JSON file in C#?
...
@RobertHarvey Liam's Json.Net link has a nice table showing what the differences are. Coming from the people that make it, of course you should take it with a grain of salt, but it is indeed better than the built-in things.
– Tim S.
...
How to prevent gcc optimizing some statements in C?
In order to make a page dirty (switching on the dirty bit in the page table entry), I touch the first bytes of the page like this:
...
How do I get the current time zone of MySQL?
...alues are not stored with timezone information in MySQL:
mysql> create table foo (tstamp datetime) Engine=MyISAM;
Query OK, 0 rows affected (0.06 sec)
mysql> insert into foo (tstamp) values (now());
Query OK, 1 row affected (0.00 sec)
mysql> set time_zone = '+01:00';
Query OK, 0 rows aff...
What is the difference between the template method and the strategy patterns?
.... Choosing which product type (class) to instantiate might depend on which tables/views it's loaded from. Strategy pattern doesn't really come into play there.
– tvanfosson
Jul 31 '15 at 16:22
...
How do I write a “tab” in Python?
...s are replaced by the intended meaning of the escape sequence.
Here is a table of some of the more useful escape sequences and a description of the output from them.
Escape Sequence Meaning
\t Tab
\\ Inserts a back slash (\)
\' Insert...
Unique BooleanField value in Django?
...d that some of them address the same issue successfully and each one is suitable in different situations:
I would choose:
@semente: Respects the constraint at the database, model and admin form levels while it overrides Django ORM the least possible. Moreover it can probably be used inside a thr...
Flask-SQLAlchemy import/context issue
... id = db.Column(db.Integer, primary_key=True)
...
# Create the database tables.
db.create_all()
...
# start the flask loop
app.run()
I just splitted one app.py to app.py and model.py without using Blueprint. In that case, the above answer dosen't work. A line code is needed to work.
before:
...
How can I merge properties of two JavaScript objects dynamically?
...ties versus just copying or defining new properties. This may make it unsuitable for merging new properties into a prototype if the merge sources contain getters." (developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/…). I had to use var merged = {...obj1, ...obj2}.
– m...