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Is it possible to implement a Python for range loop without an iterator variable?
...ou can just live with the extra i variable.
Here is the option to use the _ variable, which in reality, is just another variable.
for _ in range(n):
do_something()
Note that _ is assigned the last result that returned in an interactive python session:
>>> 1+2
3
>>> _
3
F...
How to quickly check if folder is empty (.NET)?
...
There is a new feature in Directory and DirectoryInfo in .NET 4 that allows them to return an IEnumerable instead of an array, and start returning results before reading all the directory contents.
What's New in the BCL in .NET 4 Beta 1
Directory.EnumerateFileSystemEntries method overloads
...
Generating Guids in Ruby
I have problem that is really easily solved with Guids.
10 Answers
10
...
What do the &,
Up until now I have only used database.yml with each parameter called out explicitly, in the file below it uses some characters I do not understand. What does each line and symbol(&,*,
...
Load multiple packages at once
...t retyping the require command over and over? I've tried three approaches all of which crash and burn.
10 Answers
...
Why hasn't functional programming taken over yet?
...
Because all those advantages are also disadvantages.
Stateless programs; No side effects
Real-world programs are all about side effects and mutation. When the user presses a button it's because they want something to happen. Wh...
How to get a string after a specific substring?
...("world",1)[1]
split takes the word(or character) to split on and optionally a limit to the number of splits.
In this example split on "world" and limit it to only one split.
share
|
improve thi...
How do I print the type of a variable in Rust?
...r
|
= note: expected type `()`
found type `{float}`
Or call an invalid method:
let mut my_number = 32.90;
my_number.what_is_this();
error[E0599]: no method named `what_is_this` found for type `{float}` in the current scope
--> src/main.rs:3:15
|
3 | my_number.what_is_...
Using Excel OleDb to get sheet names IN SHEET ORDER
...ABLE_NAME"].ToString();
i++;
}
// Loop through all of the sheets if you want too...
for(int j=0; j < excelSheets.Length; j++)
{
// Query each excel sheet.
}
return excelSheets;
}
catch(Exception ex)
{
return ...
Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?
...an work around it from within psql by executing the DDL statement conditionally:
SELECT 'CREATE DATABASE mydb'
WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'mydb')\gexec
The manual:
\gexec
Sends the current query buffer to the server, then treats each column of each row of the query's...