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String.replaceAll single backslashes with double backslashes
I'm trying to convert the String \something\ into the String \\something\\ using replaceAll , but I keep getting all kinds of errors. I thought this was the solution:
...
Hashing a dictionary?
...thon 3.3 returns different results between sessions). make_hashable() will convert the object into nested tuples and make_hash_sha256() will also convert the repr() to a base64 encoded SHA256 hash.
import hashlib
import base64
def make_hash_sha256(o):
hasher = hashlib.sha256()
hasher.updat...
MySQL error: key specification without a key length
... TEXT(88) simply won’t work.
The error will also pop up when you try to convert a table column from non-TEXT and non-BLOB type such as VARCHAR and ENUM into TEXT or BLOB type, with the column already been defined as unique constraints or index. The Alter Table SQL command will fail.
The solution...
SQL ON DELETE CASCADE, Which Way Does the Deletion Occur?
...have CourseID on table Category?
Maybe you should restructure your schema into this,
CREATE TABLE Categories
(
Code CHAR(4) NOT NULL PRIMARY KEY,
CategoryName VARCHAR(63) NOT NULL UNIQUE
);
CREATE TABLE Courses
(
CourseID INT NOT NULL PRIMARY KEY,
BookID INT NOT NULL,
CatCode CHAR(4) ...
Shorthand way for assigning a single field in a record, while copying the rest of the fields?
... updating record fields. In GHCi you can do --
> data Foo = Foo { a :: Int, b :: Int, c :: String } -- define a Foo
> let foo = Foo { a = 1, b = 2, c = "Hello" } -- create a Foo
> let updateFoo x = x { c = "Goodbye" } -- function to update Foos
> updateFoo foo ...
Favicon dimensions? [duplicate]
...upport possible. You upload an image and this site gives you the code, the converted images and a browserconfig file.
We could simply upload a favicon manually to our website of 16x16 and it will probably show up in almost any browser.
But when you will mark it as one of your favorites on your s...
How does '20 seconds' work in Scala?
...0.seconds()*.
Second, an "implicit conversion" is applied. Since 20 is an Int and Int has no seconds method, the compiler searches for an implicit conversion that takes an Int and returns something that does have a seconds method, with the search constrained by the scope of your method call.
You h...
Do you need to dispose of objects and set them to null?
...s Dispose() needs to implement any logic? Does it have to do something? Or internally when Dispose() is called signals GC that is good to go? I checked the source code for the TextWriter for example and Dispose has no implementation.
– Mihail Georgescu
Jan 27...
Checking if an Android application is running in the background
...e decision about what the "next" activity to go to is always done at the point where the switch is to happen, and it is not until that exact point (where the activity state is briefly locked down to do the switch) that we actually know for sure what the next thing will be.
And the implementatio...
Check whether number is even or odd
...
You can use the modulus operator, but that can be slow. If it's an integer, you can do:
if ( (x & 1) == 0 ) { even... } else { odd... }
This is because the low bit will always be set on an odd number.
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