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Python “extend” for a dictionary
...'a': 1, 'b': 2, 'c': 3, 'd': 4}
In Python 3.9 you can add two dict using union | operator
# use the merging operator |
c = a | b
# c = {'a': 1, 'b': 2, 'c': 3, 'd': 4}
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PHP validation/regex for URL
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Some things that jump out at me: use of alternation where character classes are called for (every alternative matches exactly one character); and the replacement shouldn't have needed the outer double-quotes (they were only needed because of the pointless /e modifier on the regex).
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Count occurrences of a char in plain text file
Is there any way under linux/terminal to count, how many times the char f occurs in a plain text file?
5 Answers
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How to read a file into a variable in shell?
...ther answers so far:
Trailing newline removal from command expansion
NUL character removal
Trailing newline removal from command expansion
This is a problem for the:
value="$(cat config.txt)"
type solutions, but not for read based solutions.
Command expansion removes trailing newlines:
S="...
Is there a Boolean data type in Microsoft SQL Server like there is in MySQL? [duplicate]
...compared using a comparison operator such as =, <> or IS NULL. e.g.
SELECT
a.answer_body
FROM answers AS a
WHERE a.is_accepted = 0;
From a formatting perspective, a bit value is typically displayed as 0 or 1 in client software. When a more user-friendly format is required, and it can't ...
What is a regular expression for a MAC Address?
... The second will incorrectly match strings which contain non-hex characters such as g.
– Binary Phile
Feb 25 '15 at 15:32
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Remove portion of a string after a certain character
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+1 It's the only one that works if the control characters are NOT present (unlike the others that return an empty string if the control characters are not present in the source string)
– Tom Auger
Apr 28 '15 at 2:26
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#pragma pack effect
...example, given 4-byte integers and the following struct:
struct Test
{
char AA;
int BB;
char CC;
};
The compiler could choose to lay the struct out in memory like this:
| 1 | 2 | 3 | 4 |
| AA(1) | pad.................. |
| BB(1) | BB(2) | BB(3) | BB(4) |
| CC(1) | pa...
Difference between string and text in rails?
... load varchar in one go, but store text (and blob) outside of the table. A SELECT name, amount FROM products could, be a lot slower when using text for name than when you use varchar. And since Rails, by default loads records with SELECT * FROM... your text-columns will be loaded. This will probably...
Vim: insert the same characters across multiple lines
...as the start of a text object, which is rather useful on its own, e.g. for selecting inside a tag block (it):
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