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JavaScript checking for null vs. undefined and difference between == and ===
...a === undefined)
// or
if (a == undefined) // but see note below
...but again, note that the last one is vague; it will also be true if a is null.
Now, despite the above, the usual way to check for those is to use the fact that they're falsey:
if (!a) {
// `a` is falsey, which includes `und...
Post an empty body to REST API via HttpClient
The API I'm trying to call requires that I do a POST but with an empty body. I'm new to using the WCF Web API HttpClient and I can't seem to find out the write code that would do a post with an empty body. I find references to some HttpContent.CreateEmpty() method, but I don't think that is for th...
Error while pull from git - insufficient permission for adding an object to repository database .git
I have git error: "insufficient permission for adding an object to repository database .git/objects" every time I make "git pull origin develop".
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Using Gulp to Concatenate and Uglify files
...at I needed to use gulp-rename and also output the concatenated file first before 'uglification'. Here's the code:
var gulp = require('gulp'),
gp_concat = require('gulp-concat'),
gp_rename = require('gulp-rename'),
gp_uglify = require('gulp-uglify');
gulp.task('js-fef', function(){
...
Linear Regression and group by in R
I want to do a linear regression in R using the lm() function. My data is an annual time series with one field for year (22 years) and another for state (50 states). I want to fit a regression for each state so that at the end I have a vector of lm responses. I can imagine doing for loop for each ...
Combine two ActiveRecord::Relation objects
Suppose I have the following two objects:
8 Answers
8
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How to perform a mysqldump without a password prompt?
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Since you are using Ubuntu, all you need to do is just to add a file in your home directory and it will disable the mysqldump password prompting. This is done by creating the file ~/.my.cnf (permissions need to be 600).
Add this to the .my.cn...
SQL WHERE ID IN (id1, id2, …, idn)
I need to write a query to retrieve a big list of ids.
9 Answers
9
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How to sort with lambda in Python
In Python, I am trying to sort by date with lambda. I can't understand my error message. The message is:
4 Answers
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Is an entity body allowed for an HTTP DELETE request?
When issuing an HTTP DELETE request, the request URI should completely identify the resource to delete. However, is it allowable to add extra meta-data as part of the entity body of the request?
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