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if A vs if A is not None:
...back to database stuff. There's a big difference between NULL and an empty string. An empty string typically says "there's a value here, and that value is nothing at all". NULL says "this value hasn't been entered."
In each of those cases, you'd want to use if A is None. You're checking for a speci...
Why does C++11 not support designated initializer lists as C99? [closed]
...urmountable problems with this approach; given:
struct X {
int c;
char a;
float b;
};
What order would these functions be called in in c99: struct X foo = {.a = (char)f(), .b = g(), .c = h()}? Surprisingly, in c99:
The order of evaluation of the subexpressions in any initializer i...
What should a Multipart HTTP request with multiple files look like? [duplicate]
... just to avoid any confusion: notice that before each boundary string in the content there are two extra dashes --<boundary>. For the last line is --<boundary>--
– Radu Simionescu
Jun 14 '13 at 12:03
...
How can I negate the return-value of a process?
...ns:
!(p4 labels | grep GIT_TAG_ON_A_BRANCH)
to check that the given string is not printed by 'p4 labels'.
This is problematic, because according to POSIX:
"If the pipeline begins with the reserved word ! and command1 is a subshell command, the application shall ensure that the ( o...
Convert to binary and keep leading zeros in Python
...most compact and direct option.
If you are putting the result in a larger string, use an formatted string literal (3.6+) or use str.format() and put the second argument for the format() function after the colon of the placeholder {:..}:
>>> value = 14
>>> f'The produced output, i...
Match whitespace but not newlines
... in my horizontal whitespace character class.
In Java:
static public final String HORIZONTAL_WHITESPACE = "[\\p{Blank}\\u200B\\u2060\\uFFEF]"
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npm not working - “read ECONNRESET”
...ured. Strangely enough, mine did come with a proxy defined, pointing to an IP and port 3128. Removing the proxy did the trick.
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Parse JSON String into a Particular Object Prototype in JavaScript
I know how to parse a JSON String and turn it into a JavaScript Object.
You can use JSON.parse() in modern browsers (and IE9+).
...
Best way to strip punctuation from a string
...om an efficiency perspective, you're not going to beat
s.translate(None, string.punctuation)
For higher versions of Python use the following code:
s.translate(str.maketrans('', '', string.punctuation))
It's performing raw string operations in C with a lookup table - there's not much that will...
Create an array with same element repeated multiple times
...ate (05/11/2019):
Another way, without using fill or from, that works for string of any length:
Array.apply(null, Array(3)).map(_ => 'abc') // ['abc', 'abc', 'abc']
Same as above answer. Adding for sake of completeness.
...