No error , No gain

After I upgraded to the latest stable node and npm, I tried npm install moment --save. It saves the entry in the package.json with the caret ^ prefix. Previously, it was a tilde ~ prefix. Why are these changes made in npm? What is the difference between tilde ~ and caret ^? What are the advantages over others? See the NPM docs and semver docs: ~version “Approximately equivalent to version”, will..

How can I add a blank directory (that contains no files) to a Git repository? Another way to make a directory stay (almost) empty (in the repository) is to create a .gitignore file inside that directory that contains these four lines: # Ignore everything in this directory * # Except this file !.gitignore Then you don't have to get the order right the way that you have to do in m104's solution. T..

Is there a shortcut to make a simple list out of a list of lists in Python? I can do it in a for loop, but is there some cool "one-liner"? I tried it with functools.reduce(): from functools import reduce l = [[1, 2, 3], [4, 5, 6], [7], [8, 9]] reduce(lambda x, y: x.extend(y), l) But I get this error: Traceback (most recent call last): File "", line 1, in File "", line 1, in AttributeError: 'None..

I have a master and a development branch, both pushed to GitHub. I've cloned, pulled, and fetched, but I remain unable to get anything other than the master branch back. I'm sure I'm missing something obvious, but I have read the manual and I'm getting no joy at all. First, clone a remote Git repository and cd into it: $ git clone git://example.com/myproject $ cd myproject Next, look at the loca..

How do I access the index in a for loop like the following? ints = [8, 23, 45, 12, 78] for i in ints: print('item #{} = {}'.format(???, i)) I want to get this output: item #1 = 8 item #2 = 23 item #3 = 45 item #4 = 12 item #5 = 78 When I loop through it using a for loop, how do I access the loop index, from 1 to 5 in this case? Using an additional state variable, such as an index variable (which..

I need a good explanation (references are a plus) on Python's slice notation. To me, this notation needs a bit of picking up. It looks extremely powerful, but I haven't quite got my head around it. It's pretty simple really: a[start:stop] # items start through stop-1 a[start:] # items start through the rest of the array a[:stop] # items from the beginning through stop-1 a[:] # a copy of the whol..

What is the most concise and efficient way to find out if a JavaScript array contains a value? This is the only way I know to do it: function contains(a, obj) { for (var i = 0; i < a.length; i++) { if (a[i] === obj) { return true; } } return false; } Is there a better and more concise way to accomplish this? Modern browsers have Array#includes, which does exactly that and is widely supported by ..

I know it's possible to match a word and then reverse the matches using other tools (e.g. grep -v). However, is it possible to match lines that do not contain a specific word, e.g. hede, using a regular expression? Input: hoho hihi haha hede Code: grep "[^R]+|R+(?!egex Hero))*$ resulting in a small performance gain. But the overall most readable and performance-wise fastest solution seems to be ..

Yesterday I was pairing the socks from the clean laundry and figured out the way I was doing it is not very efficient. I was doing a naive search — picking one sock and "iterating" the pile in order to find its pair. This requires iterating over n/2 * n/4 = n2/8 socks on average. As a computer scientist I was thinking what I could do? Sorting (according to size/color/...) of course came to mind ..

How can I squash my last X commits together into one commit using Git? You can do this fairly easily without git rebase or git merge --squash. In this example, we'll squash the last 3 commits. If you want to write the new commit message from scratch, this suffices: git reset --soft HEAD~3 && git commit If you want to start editing the new commit message with a concatenation of the existing commi..