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Comparing two dictionaries and checking how many (key, value) pairs are equal
...th possibly different attribute values as in the example). However, if an "extra" attribute is present is one of the dicts, json.dumps() fails with
TypeError: Object of type PrettyOrderedSet is not JSON serializable
Solution: use diff.to_json() and json.loads() / json.dumps() to pretty-print:
im...
What does the `forall` keyword in Haskell/GHC do?
... b)
ghci> liftTup (\x -> [x]) (5, "Hello")
No instance for (Num [Char])
...
ghci> -- huh?
ghci> :t liftTup
liftTup :: (t -> t1) -> (t, t) -> (t1, t1)
"Hmm.. why does GHC infer that the tuple must contain two of the same type? Let's tell it they don't have to be"
-- te...
When saving, how can you check if a field has changed?
...
Really perfect, and do not perform extra query. Thanks a lot !
– Stéphane
Mar 4 '13 at 10:26
29
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How to replace a hash key with another key
...
If all the keys are strings and all of them have the underscore prefix, then you can patch up the hash in place with this:
h.keys.each { |k| h[k[1, k.length - 1]] = h[k]; h.delete(k) }
The k[1, k.length - 1] bit grabs all of k except the firs...
Odd behavior when Java converts int to byte?
...e number as negative
public class castingsample{
public static void main(String args[]){
int i;
byte y;
i = 1024;
for(i = 1024; i > 0; i-- ){
y = (byte)i;
System.out.print(i + " mod 128 = " + i%128 + " also ");
System.out.println(i + " cast to byte " + " = " ...
Converting String to Int with Swift
...to calculate acceleration. However, since the values in the text boxes are string, I am unable to convert them to integers.
...
How to split a comma-separated value to columns
...
CREATE FUNCTION [dbo].[fn_split_string_to_column] (
@string NVARCHAR(MAX),
@delimiter CHAR(1)
)
RETURNS @out_put TABLE (
[column_id] INT IDENTITY(1, 1) NOT NULL,
[value] NVARCHAR(MAX)
)
AS
BEGIN
DECLARE @value NVARCHAR(MAX),
...
Or versus OrElse
... the right operand won't even be evaluated (this is useful in cases like:
string a;
//...
if (a is null) or (a = "Hi") //...
to avoid a NullReferenceException throw by the right-hand operand.
I'm sincerely astonished that this (lazy evaluation) isn't the default behaviour of or and and as it is ...
Make a link use POST instead of GET
... tab to the url of the href
As the method is POST, we should have no query string in the URL of the target page we load
That page should receive the data in parameters (names and value) by POST
I am using jquery here, but this could be done with native apis (harder and longer of course).
<html...
How do I remove the first characters of a specific column in a table?
... - 4) AS MyTrimmedColumn
Edit:
To explain, RIGHT takes 2 arguments - the string (or column) to operate on, and the number of characters to return (starting at the "right" side of the string). LEN returns the length of the column data, and we subtract four so that our RIGHT function leaves the lef...