大约有 40,000 项符合查询结果(耗时:0.0531秒) [XML]

https://stackoverflow.com/ques... 

How to turn on/off ReactJS 'development mode'?

...me helpers off during production. Just using the minified react will leave all those potential optimizations on the table as well. Ultimately the magic comes down to React embedding references to process.env.NODE_ENV throughout the codebase; these act like a feature toggle. if (process.env.NODE_ENV ...
https://stackoverflow.com/ques... 

Programmatically generate video or animated GIF in Python?

I have a series of images that I want to create a video from. Ideally I could specify a frame duration for each frame but a fixed frame rate would be fine too. I'm doing this in wxPython, so I can render to a wxDC or I can save the images to files, like PNG. Is there a Python library that will al...
https://stackoverflow.com/ques... 

Pandas - How to flatten a hierarchical index in columns

..., but leaves behind column names which are difficult to access programmatically and are not queriable – dmeu Jun 29 '17 at 8:53 1 ...
https://stackoverflow.com/ques... 

How to remove an item from an array in AngularJS scope?

... Your issue is not really with Angular, but with Array methods. The proper way to remove a particularly item from an array is with Array.splice. Also, when using ng-repeat, you have access to the special $index property, which is the current inde...
https://stackoverflow.com/ques... 

How can I check for Python version in a program that uses new language features?

...rom the question that needed addressing is that a program must be syntactically correct for that version of python to even begin executing, so using new syntax precludes a program from starting on older versions of the interpreter. eval works around that – Autoplectic ...
https://stackoverflow.com/ques... 

Test if a variable is a list or tuple

... excludes custom sequences, iterators, and other things that you might actually need. However, sometimes you need to behave differently if someone, for instance, passes a string. My preference there would be to explicitly check for str or unicode like so: import types isinstance(var, types.String...
https://stackoverflow.com/ques... 

How to track down a “double free or corruption” error

... If you're using glibc, you can set the MALLOC_CHECK_ environment variable to 2, this will cause glibc to use an error tolerant version of malloc, which will cause your program to abort at the point where the double free is done. You can set this from gdb by using ...
https://stackoverflow.com/ques... 

How to remove non-alphanumeric characters?

I need to remove all characters from a string which aren't in a-z A-Z 0-9 set or are not spaces. 9 Answers ...
https://stackoverflow.com/ques... 

What's the difference between using CGFloat and float?

I tend to use CGFloat all over the place, but I wonder if I get a senseless "performance hit" with this. CGFloat seems to be something "heavier" than float, right? At which points should I use CGFloat, and what makes really the difference? ...
https://stackoverflow.com/ques... 

How to take the first N items from a generator or list in Python? [duplicate]

...imple syntax: array[start:stop:step] You can omit any parameter. These are all valid: array[start:], array[:stop], array[::step] Slicing a generator import itertools top5 = itertools.islice(my_list, 5) # grab the first five elements You can't slice a generator directly in Python. itertools.i...