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Why is there an injected class name?
... to refer to the current instantiation. See DR 176 for a change between C++98 and C++03 that clarified that.
The idea of the injected class name was present in C++98, but the terminology was new for C++03.
C++98 says:
A class-name is inserted into the scope in which it is declared immediately ...
How to convert a string to number in TypeScript?
...rrect typing and will correctly parse simple decimal integer strings like "123", but will behave differently for various other, possibly expected, cases (like "123.45") and corner cases (like null).
Table taken from this answer
...
unable to start mongodb local server
...s Jung:
"Sat Jun 25 09:38:51 [initandlisten] listen(): bind() failed errno:98 Address already in use for socket: 0.0.0.0:27017
is self-speaking.
Another instance of mongod is already running and allocating the MongoDB default port which is 27017.
Either kill the other process or use a different port...
MySQL Conditional Insert
...nsert, try:
INSERT INTO x_table(instance, user, item)
SELECT 919191, 123, 456
FROM dual
WHERE NOT EXISTS (SELECT * FROM x_table
WHERE user = 123
AND item = 456)
In this, dual is a table with one row only (found orig...
How to find elements with 'value=x'?
I need to remove element that have value="123" . I know that all elements with different values are located into #attached_docs , but I don't know how to select element with value="123" .
...
vs
...
123
The original intention in C++98 was that you should use <cstdint> in C++, to avoid pollu...
Difference between matches() and find() in Java Regex
...
Pattern p = Pattern.compile("\\d\\d\\d");
Matcher m = p.matcher("a123b");
System.out.println(m.find());
System.out.println(m.matches());
p = Pattern.compile("^\\d\\d\\d$");
m = p.matcher("123");
System.out.println(m.find());
System.out.println(m.matches());
}
/* ou...
Fastest way to convert string to integer in PHP
Using PHP, what's the fastest way to convert a string like this: "123" to an integer?
8 Answers
...
Simple Pivot Table to Count Unique Values
...s two different columns. Using the original example, I didn't have:
ABC 123
ABC 123
ABC 123
DEF 456
DEF 567
DEF 456
DEF 456
and want it to appear as:
ABC 1
DEF 2
But something more like:
ABC 123
ABC 123
ABC 123
ABC 456
DEF 123
DEF 456
D...
Which is faster in Python: x**.5 or math.sqrt(x)?
... (Python 2.5.2, Windows):
$ python -mtimeit -s"from math import sqrt; x = 123" "x**.5"
1000000 loops, best of 3: 0.445 usec per loop
$ python -mtimeit -s"from math import sqrt; x = 123" "sqrt(x)"
1000000 loops, best of 3: 0.574 usec per loop
$ python -mtimeit -s"import math; x = 123" "math.sqrt(x...