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How to check if a string is a valid date
I have a string: "31-02-2010" and want to check whether or not it is a valid date.
What is the best way to do it?
14 Answ...
Get model's fields in Django
... and each element is a Model field type, which can't be used directly as a string. So, field.name will return the field name
my_model_fields = [field.name for field in MyModel._meta.get_fields()]
The above code will return a list conatining all fields name
Example
In [11]: from django.contrib.aut...
How to “EXPIRE” the “HSET” child key in redis?
...d zset Redis objects under the hood. Usage example:
RMapCache<Integer, String> map = redisson.getMapCache('map');
map.put(1, 30, TimeUnit.DAYS); // this entry expires in 30 days
This approach is quite useful.
share
...
How does Hadoop process records split across block boundaries?
...ow away first record
// because we always (except the last split) read one extra line in
// next() method.
if (start != 0) {
start += in.readLine(new Text(), 0, maxBytesToConsume(start));
}
this.pos = start;
from this I believe hadoop will read one extra line for each split(at the end of current...
In Scala, what exactly does 'val a: A = _' (underscore) mean?
...
val a: A = _ is a compile error. For example:
scala> val a: String = _
<console>:1: error: unbound placeholder parameter
val a: String = _
^
What does work is var a: A = _ (note var instead of val). As Chuck says in his answer, this initialises th...
Ruby, remove last N characters from a string?
What is the preferred way of removing the last n characters from a string?
13 Answers
...
Get absolute path of initially run script
...h under some circumstances." plus "dirname() operates naively on the input string, and is not aware of the actual filesystem, or path components such as '..'.
– rik
Jan 10 '11 at 9:49
...
Why is __dirname not defined in node REPL?
...
path.dirname seems to not accept non-string values anymore in the newest major version, 6.0.0, so the first suggestion in this answer will not work.
– trysis
Jun 16 '16 at 15:22
...
Wolfram's Rule 34 in XKCD [closed]
...n a cellular automaton (CA) that follows rule 2, then whenever a three-bit string matches rule 2's configuration, the center bit becomes (or stays, in this case) true on the next iteration.
A CA's rules are described as a bitstring. Say it's rule 110 (my favorite). In binary, 110 is 01101110. The d...
Execution of Python code with -m option or not
...east the possibility of a package, so the __package__ variable is set to a string value; in the above demonstration it is set to 'foo.bar', for plain modules not inside a package it is set to an empty string.
As for the __main__ module, Python imports scripts being run as it would import regular mod...