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What are type lambdas in Scala and what are their benefits?
...ction of Either[A, B]. The monad typeclass looks like this:
trait Monad[M[_]] {
def point[A](a: A): M[A]
def bind[A, B](m: M[A])(f: A => M[B]): M[B]
}
Now, Either is a type constructor of two arguments, but to implement Monad, you need to give it a type constructor of one argument. The sol...
Importing a CSV file into a sqlite3 database table using Python
...csv, sqlite3
con = sqlite3.connect(":memory:") # change to 'sqlite:///your_filename.db'
cur = con.cursor()
cur.execute("CREATE TABLE t (col1, col2);") # use your column names here
with open('data.csv','r') as fin: # `with` statement available in 2.5+
# csv.DictReader uses first line in file fo...
TypeError: 'module' object is not callable
...\Python27\lib\socket.pyc'>
>>> socket.socket
<class 'socket._socketobject'>
>>>
>>> from socket import socket
>>> socket
<class 'socket._socketobject'>
This is what the error message means:
It says module object is not callable, because your code ...
Is there a way to include commas in CSV columns without breaking the formatting?
...
Enclose the field in quotes, e.g.
field1_value,field2_value,"field 3,value",field4, etc...
See wikipedia.
Updated:
To encode a quote, use ", one double quote symbol in a field will be encoded as "", and the whole field will become """". So if you see the follow...
Make Bootstrap Popover Appear/Disappear on Hover instead of Click
... placement: 'auto'
}).on("mouseenter",function () {
var _this = this; // thumbcontainer
console.log('thumbcontainer mouseenter')
// clear the counter
clearTimeout(counter);
// Close all other Popovers
$('.thumbcontainer').not(_this).popover...
Stop “developer tools access needs to take control of another process for debugging to continue” ale
...ict>
- <key>group</key>
- <string>_developer</string>
<key>shared</key>
<true/>
- <key>timeout</key>
- <integer>36000</integer>
+ <key>k-of-n</key&g...
Remove last item from array
...
learn by example:
let array_1 = [1,2,3,4];
let array_2 = [1,2,3,4];
let array_3 = [1,2,3,4];
array_1.splice(-1,1) // output --> [4] array_1 = [1,2,3]
array_2.slice(0,-1); // output --> [1,2,3] array_2 = [1,2,3,4]
array_3.pop(); //...
Any way to delete in vim without overwriting your last yank? [duplicate]
...
Pass to the _ register, the black hole.
To delete a line without sticking it in the registers:
"_dd
See also :help registers.
It's probably safest, if you want to paste something over and over again, to yank it into a "named" regist...
What is the use of having destructor as private?
...e connection being open or a file being written. You could have a "request_delete" method in the class or the manager that will check that condition and it will either delete or decline, and return a status telling you what it did. That's far more flexible that just calling "delete".
...
Call one constructor from another
...
@ivan_pozdeev: Yes, you can; use ?: or call a static method.
– SLaks
Oct 12 '14 at 1:17
3
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