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How to quickly check if folder is empty (.NET)?
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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
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Determine if Python is running inside virtualenv
...r sys.base_prefix did not ever exist. So a fully robust check that handles all of these cases could look like this:
import sys
def get_base_prefix_compat():
"""Get base/real prefix, or sys.prefix if there is none."""
return getattr(sys, "base_prefix", None) or getattr(sys, "real_prefix", No...
Arduino Sketch upload issue - avrdude: stk500_recv(): programmer is not responding
...it works. I figured the packets were some attempt at a hand-shake. So basically, I solved it using Google, patience and futzing around with the board!
– hoipolloi
Jan 12 '14 at 18:16
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How do I use extern to share variables between source files?
...ler is informed that a
variable exists (and this is its type); it does not allocate the
storage for the variable at that point.
A variable is defined when the compiler allocates the storage for
the variable.
You may declare a variable multiple times (though once is sufficient);
you may only defin...
What happens if you don't commit a transaction to a database (say, SQL Server)?
...ou don't COMMIT or ROLLBACK a transaction, it's still "running" and potentially holding locks.
If your client (application or user) closes the connection to the database before committing, any still running transactions will be rolled back and terminated.
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Creating C formatted strings (not printing them)
...ee snprintf for a safer version).
A terminating null character is automatically appended after the
content.
After the format parameter, the function expects at least as many
additional arguments as needed for format.
Parameters:
str
Pointer to a buffer where the resulting C-string is stored. The ...
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
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Have a reloadData for a UITableView animate when changing
...the modes I have a different number of sections and cells per section. Ideally, it would do some cool animation when the table grows or shrinks.
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Swift equivalent for MIN and MAX macros
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With Swift 5, max(_:_:) and min(_:_:) are part of the Global Numeric Functions. max(_:_:) has the following declaration:
func max<T>(_ x: T, _ y: T) -> T where T : Comparable
You can use it like this with Ints:
let maxInt = max(5,...
How do I print the type of a variable in Rust?
...r
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= 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
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3 | my_number.what_is_...