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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...
Dynamically creating keys in a JavaScript associative array
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Assuming the text string actually does have the curly braces, you could more or less treat it as JSON.. replace the = sign with a : and you've got an object to eval..
– neonski
Dec 9 '08 at 3:15
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PostgreSQL function for last inserted ID
...s some TRIGGER (or RULE) that, on insertion into persons table, makes some extra insertions in other tables... then LASTVAL will probably give us the wrong value. The problem can even happen with CURRVAL, if the extra insertions are done intto the same persons table (this is much less usual, but the...
How do you serialize a model instance in Django?
...ou have a completely flat data structure (no ForeignKeys, only numbers and strings in the database, etc.). Otherwise, you should seriously think about the right way to implement this method.
Third, call demjson.JSON.encode(instance) and you have what you want.
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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...
C# List to string with delimiter
Is there a function in C# to quickly convert some collection to string and separate values with delimiter?
2 Answers
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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 a CSS rule / class with jQuery at runtime
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.appendTo("head");
Noticed the back slashes? They are used to join strings that are on new lines. Leaving them out generates an error.
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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.
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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+).
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