大约有 40,000 项符合查询结果（耗时：0.0346秒） [XML]
Is it possible to implement a Python for range loop without an iterator variable?
...ou can just live with the extra i variable.
Here is the option to use the _ variable, which in reality, is just another variable.
for _ in range(n):
do_something()
Note that _ is assigned the last result that returned in an interactive python session:
>>> 1+2
3
>>> _
3
F...
Counting array elements in Python [duplicate]
... out as 2, as does len(array([[0, 0], [0, 0]])).
– EL_DON
Jan 19 '18 at 22:49
how about index of array? for example, w...
How to write inline if statement for print?
... condition:
block
if expression (introduced in Python 2.5)
expression_if_true if condition else expression_if_false
And note, that both print a and b = a are statements. Only the a part is an expression. So if you write
print a if b else 0
it means
print (a if b else 0)
and similarly ...
Installing Python packages from local file system folder to virtualenv with pip
...
The equivalent easy_install command is easy_install --allow-hosts=None --find-links file:///srv/pkg/mypackage mypackage
– Wilfred Hughes
Dec 13 '17 at 16:23
...
Remove all occurrences of a value from a list?
...ython 3.x
>>> x = [1,2,3,2,2,2,3,4]
>>> list(filter((2).__ne__, x))
[1, 3, 3, 4]
or
>>> x = [1,2,3,2,2,2,3,4]
>>> list(filter(lambda a: a != 2, x))
[1, 3, 3, 4]
Python 2.x
>>> x = [1,2,3,2,2,2,3,4]
>>> filter(lambda a: a != 2, x)
[1, 3, 3...
How does functools partial do what it does?
...g like this (apart from keyword args support etc):
def partial(func, *part_args):
def wrapper(*extra_args):
args = list(part_args)
args.extend(extra_args)
return func(*args)
return wrapper
So, by calling partial(sum2, 4) you create a new function (a callable, to b...
rails i18n - translating text with links inside
...
en.yml
log_in_message_html: "This is a text, with a %{href} inside."
log_in_href: "link"
login.html.erb
<p> <%= t("log_in_message_html", href: link_to(t("log_in_href"), login_path)) %> </p>
...
Override Python's 'in' operator?
...
MyClass.__contains__(self, item)
share
|
improve this answer
|
follow
|
...
Mongoose, Select a specific field with find
...
The _id field is always present unless you explicitly exclude it. Do so using the - syntax:
exports.someValue = function(req, res, next) {
//query with mongoose
var query = dbSchemas.SomeValue.find({}).select('name -_id'...
Python's equivalent of && (logical-and) in an if-statement
...actually
evaluated because of the print statements:
>>> def print_and_return(value):
... print(value)
... return value
>>> res = print_and_return(False) and print_and_return(True)
False
As you can see only one print statement is executed, so Python really didn't even lo...