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How do you use the ellipsis slicing syntax in Python?
...'d use it like this:
>>> class TestEllipsis(object):
... def __getitem__(self, item):
... if item is Ellipsis:
... return "Returning all items"
... else:
... return "return %r items" % item
...
>>> x = TestEllipsis()
>>> print ...
Subprocess changing directory
...
@The_Diver That's why cd must be implemented as internal shell command. There's no other way to do it. Internal shell commands are executed within the same process as the shell. What I meant by subshell is the shell executed for ...
What is the most efficient way to deep clone an object in JavaScript?
...actical.
class StructuredCloner {
constructor() {
this.pendingClones_ = new Map();
this.nextKey_ = 0;
const channel = new MessageChannel();
this.inPort_ = channel.port1;
this.outPort_ = channel.port2;
this.outPort_.onmessage = ({data: {key, value}}) => {
const r...
What is a proper naming convention for MySQL FKs?
...ue name automatically.
In any case, this is the convention that I use:
fk_[referencing table name]_[referenced table name]_[referencing field name]
Example:
CREATE TABLE users(
user_id int,
name varchar(100)
);
CREATE TABLE messages(
message_id int,
user_id int
);
...
Why do I get a segmentation fault when writing to a “char *s” initialized with a string literal, but
...the pointer to void * as in printf("%p", (void *)str); When printing a size_t with printf, you should use "%zu" if using the latest C standard (C99).
– Chris Young
Oct 3 '08 at 7:44
...
Android Gallery on Android 4.4 (KitKat) returns different URI for Intent.ACTION_GET_CONTENT
Before KitKat (or before the new Gallery) the Intent.ACTION_GET_CONTENT returned a URI like this
19 Answers
...
How to print to stderr in Python?
...ound this to be the only one short + flexible + portable + readable:
from __future__ import print_function
import sys
def eprint(*args, **kwargs):
print(*args, file=sys.stderr, **kwargs)
The function eprint can be used in the same way as the standard print function:
>>> print("Test...
Is nested function a good approach when required by only one function? [closed]
...
>>> def sum(x, y):
... def do_it():
... return x + y
... return do_it
...
>>> a = sum(1, 3)
>>> a
<function do_it at 0xb772b304>
>>> a()
4
Is this what you were looking for? It's called a closure.
...
What is the difference between char array and char pointer in C?
...sizeof(q)); // => size of char array in memory -- 6 on both
// size_t strlen(const char *s) and we don't get any warnings here:
printf("%zu\n", strlen(p)); // => 5
printf("%zu\n", strlen(q)); // => 5
return 0;
}
foo* and foo[] are different types and they are handled dif...
Remove blank attributes from an Object in Javascript
...a simple solution:
var obj = {name: 'John', age: null};
var compacted = _.pickBy(obj);
This will only work with lodash 4, pre lodash 4 or underscore.js, use _.pick(obj, _.identity);
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