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1500 questions
6018
votes
66 answers
How do I execute a program or call a system command?
How do I call an external command within Python as if I had typed it in a shell or command prompt?
freshWoWer
- 61,969
- 10
- 36
- 35
5649
votes
48 answers
Which equals operator (== vs ===) should be used in JavaScript comparisons?
I'm using JSLint to go through JavaScript, and it's returning many suggestions to replace == (two equals signs) with === (three equals signs) when doing things like comparing idSele_UNVEHtype.value.length == 0 inside of an if statement.
Is there a…
bcasp
- 57,397
- 4
- 19
- 15
5642
votes
18 answers
What is the maximum length of a URL in different browsers?
What is the maximum length of a URL for each browser?
Is a maximum URL length part of the HTTP specification?
Sander Versluys
- 72,737
- 23
- 84
- 91
5639
votes
36 answers
How do I reset or revert a file to a specific revision?
How do I revert a modified file to its previous revision at a specific commit hash (which I determined via git log and git diff)?
Hates_
- 66,613
- 6
- 32
- 37
5616
votes
41 answers
Loop (for each) over an array in JavaScript
How can I loop through all the entries in an array using JavaScript?
Dante1986
- 58,291
- 13
- 39
- 54
5551
votes
27 answers
How do I create a directory, and any missing parent directories?
How do I create a directory at a given path, and also create any missing parent directories along that path? For example, the Bash command mkdir -p /path/to/nested/directory does this.
Parand
- 102,950
- 48
- 151
- 186
5550
votes
18 answers
How do I push a new local branch to a remote Git repository and track it too?
How do I:
Create a local branch from another branch (via git branch or git checkout -b).
Push the local branch
to the remote repository (i.e. publish), but make it
trackable so that git pull and git push will work.
Roni Yaniv
- 57,651
- 5
- 19
- 16
5537
votes
27 answers
Reset local repository branch to be just like remote repository HEAD
How do I reset my local branch to be just like the branch on the remote repository?
I tried:
git reset --hard HEAD
But git status claims I have modified files:
On branch master
Changes to be committed:
(use "git reset HEAD ..." to unstage)
…
hap497
- 154,439
- 43
- 83
- 99
5518
votes
11 answers
The definitive guide to form-based website authentication
Moderator note:
This question is not a good fit for our question and answer format with the topicality rules which currently apply for Stack Overflow. We normally use a "historical lock" for such questions where the content still has value.…
Michiel de Mare
- 41,982
- 29
- 103
- 134
5476
votes
79 answers
How can I validate an email address in JavaScript?
I'd like to check if the user input is an email address in JavaScript, before sending it to a server or attempting to send an email to it, to prevent the most basic mistyping. How could I achieve this?
pix0r
- 31,139
- 18
- 86
- 102
5404
votes
78 answers
How do I replace all occurrences of a string in JavaScript?
Given a string:
s = "Test abc test test abc test test test abc test test abc";
This seems to only remove the first occurrence of abc in the string above:
s = s.replace('abc', '');
How do I replace all occurrences of it?
Ali
- 261,656
- 265
- 575
- 769
5342
votes
43 answers
What is a plain English explanation of "Big O" notation?
I'd prefer as little formal definition as possible and simple mathematics.
Arec Barrwin
- 61,343
- 9
- 29
- 25
5331
votes
36 answers
How do I resolve merge conflicts in a Git repository?
How do I resolve merge conflicts in my Git repository?
Spoike
- 119,724
- 44
- 140
- 158
5310
votes
27 answers
How to determine the URL that a local Git repository was originally cloned from
I pulled a project with several forks on GitHub, but forgot which fork it was. How do I determine which fork I pulled?
Tim
- 53,399
- 3
- 19
- 19
5275
votes
34 answers
Regular expression to match a line that doesn't contain a word
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…
knaser
- 1,421
- 7
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- 16