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Monad in plain English? (For the OOP programmer with no FP background)
...on, that composition is associative, and so on.
In C#, "Bind" is called "SelectMany". Take a look at how it works on the sequence monad. We need to have two things: turn a value into a sequence and bind operations on sequences. As a bonus, we also have "turn a sequence back into a value". Those op...
Filter rows which contain a certain string
... @MySchizoBuddy: If the column name contains white space, you can select the variable using backticks. Modifying the example above: mtcars$`my type` <- rownames(mtcars) and then mtcars %>% filter(grepl('Toyota|Mazda', `my type`))
– alex23lemm
Ju...
What is the difference between required and ng-required?
...ld B - say, a student number - if the field A has a certain value - if you selected "student" as a choice)
As an example, <input required> and <input ng-required="true"> are essentially the same thing
If you are wondering why this is this way, (and not just make <input required="tru...
Difference between GIT and CVS
...neral distributed version control systems, such as Git, provide much wider selection of possible workflows. With centralized version control systems, such as CVS, by necessity you have to distinguish between people with commit access to repository, and those without... and CVS doesn't offer any tool...
Example of multipart/form-data
... > a.html
Run:
nc -l localhost 8000
Open the HTML on your browser, select the files and click on submit and check the terminal.
nc prints the request received. Firefox sent:
POST / HTTP/1.1
Host: localhost:8000
User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:29.0) Gecko/20100101 Fire...
PDO Prepared Inserts multiple rows in single query
... INSERT statements instead of building out as a single string query as the selected answer did. I decided to run a simple test with just two fields and a very basic insert statement:
<?php
require('conn.php');
$fname = 'J';
$lname = 'M';
$time_start = microtime(true);
$stmt = $db->prepare('...
How can I add a third button to an Android Alert Dialog?
...'which' argument contains the index position
// of the selected item
switch (which) {
case 0:
Toast.makeText(context, "clicked 1", 0).show();
break;
case 1:...
How to profile a bash shell script slow startup?
...e set -x later and set +x earlier (or bracket several sections of interest selectively).
Although it's not as fine-grained as GNU date's nanoseconds, Bash 5 includes a variable which gives the time in microseconds. Using it saves you from spawning an external executable for every line and works on ...
Why does an NSInteger variable have to be cast to long when used as a format argument?
...
I suppose the selected answer is technically the best answer to the question, but if you want to know how to avoid casting each occurrence and prevent warnings then I find this is the best solution.
– Daniel Wood
...
Match multiple cases classes in scala
...either sb or sc get bound, but you don't know which, so you'd need further selection logic to decide which to use (given that they were bound to a Option[String], not a String). So there's nothing gained over this:
l match {
case A() => "A"
case B(sb) => "B(" + sb + ")"
case C(s...