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Functions that return a function
... return any object from a function. You can return a true/false value. An integer (1,2,3,4...). You can return a string. You can return a complex object with multiple properties. And you can return a function. a function is just a thing.
In your case, returning b returns the thing, the thing...
How to get rid of `deprecated conversion from string constant to ‘char*’` warnings in GCC?
...
Any functions into which you pass string literals "I am a string literal" should use char const * as the type instead of char*.
If you're going to fix something, fix it right.
Explanation:
You can not use string literals to initialise s...
Should an Enum start with a 0 or a 1?
...stic trade off I guess - disk space is cheap though, time spent constantly converting between enum values and an intwhen searching the db is relatively expensive (doubly so if you have a reporting tool setup against a database or something similar). If you're worried abotu space, with the newer SQL ...
How do you set the text in an NSTextField?
...ng to set happens to be an integer rather than a string, you don't need to convert the integer value to a string manually; you can just call:
myLabel.integerValue = i;
The integerValue property is defined on NSTextField's parent class, NSControl. See that linked documentation page for a full list...
PostgreSQL Autoincrement
... equivalent function.
CREATE TABLE foo (
id SERIAL,
bar varchar);
INSERT INTO foo (bar) values ('blah');
INSERT INTO foo (bar) values ('blah');
SELECT * FROM foo;
1,blah
2,blah
SERIAL is just a create table time macro around sequences. You can not alter SERIAL onto an existing column.
...
How do I use reflection to invoke a private method?
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I am going to get myself into so much trouble with this.
– Frank Schwieterman
Mar 10 '09 at 18:10
2
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How to get the current time as datetime
...s this:
let currentDateTime = Date()
However, Date is a 64-bit floating point number measuring the number of seconds since the reference date of January 1, 2001 at 00:00:00 UTC. I can see that number for the current datetime by using
Date().timeIntervalSinceReferenceDate
At the time of this writin...
What does the “__block” keyword mean?
...s Blocks Programming Topics.
The important example is this one:
extern NSInteger CounterGlobal;
static NSInteger CounterStatic;
{
NSInteger localCounter = 42;
__block char localCharacter;
void (^aBlock)(void) = ^(void) {
++CounterGlobal;
++CounterStatic;
Count...
In Ruby how do I generate a long string of repeated text?
...ts. It certainly could (for example, automatically making a best-effort to convert the argument to a FixNum) but the language designers decided against embracing Ruby's Perlish inspirations too fully.
– FMc
Jan 15 '17 at 2:12
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How to toggle a value in Python
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The not operator negates your variable (converting it into a boolean if it isn't already one). You can probably use 1 and 0 interchangeably with True and False, so just negate it:
toggle = not toggle
But if you are using two arbitrary values, use an inline if:
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