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Best way to iterate through a Perl array
...C instead of Perl, and no needless copying of the array elements occurs. ($_ is aliased to the element in #1, but #2 and #3 actually copy the scalars from the array.)
#5 might be similar.
In terms memory usage: They're all the same except for #5.
for (@a) is special-cased to avoid flattening the a...
What's the cause of this FatalExecutionEngineError in .NET 4.5 beta? [closed]
...d .cctor() cil managed
{
// Code size 11 (0xb)
.maxstack 8
IL_0000: ldstr ""
IL_0005: stsfld string System.String::Empty
IL_000a: ret
} // end of method String::.cctor
In the .NET 4.5 version of mscorlib.dll, String.cctor (the static constructor) is conspicuously abse...
How do I dump an object's fields to the console?
...well, but it can be really useful when debugging. Ruby will fall back to to_s if it can't find an inspect` method.
– the Tin Man
Nov 27 '10 at 21:45
...
C# pattern to prevent an event handler hooked twice [duplicate]
...ution and the best one (considering performance) is:
private EventHandler _foo;
public event EventHandler Foo {
add {
_foo -= value;
_foo += value;
}
remove {
_foo -= value;
}
}
No Linq using required. No need to check for null before cancelling a subscrip...
Objective-C and Swift URL encoding
...*)CFBridgingRelease(CFURLCreateStringByAddingPercentEscapes(
NULL,
(__bridge CFStringRef) unescaped,
NULL,
CFSTR("!*'();:@&=+$,/?%#[]\" "),
kCFStringEncodingUTF8));
Using Core Foundation Without ARC:
NSString *escapedString = (NSString *)CFURLCreateStringByAddingPercentEs...
How to select a single field for all documents in a MongoDB collection?
...uery. In the result set, only the item and qty fields and, by default, the _id field return in the matching documents.
db.inventory.find( { type: 'food' }, { item: 1, qty: 1 } )
In this example from the folks at Mongo, the returned documents will contain only the fields of item, qty, and _id.
Thus...
Why use apparently meaningless do-while and if-else statements in macros?
...mi-colon. Should the user view code not needing one...
doSomething(1) ;
DO_SOMETHING_ELSE(2) // <== Hey? What's this?
doSomethingElseAgain(3) ;
This means the user expects the compiler to produce an error if the semi-colon is absent.
But the real real good reason is that at some time, the ma...
How to match a String against string literals in Rust?
...intln!("0"),
"b" => println!("1"),
"c" => println!("2"),
_ => println!("something else!"),
}
There's also an as_str method as of Rust 1.7.0:
match stringthing.as_str() {
"a" => println!("0"),
"b" => println!("1"),
"c" => println!("2"),
_ => println...
clear javascript console in Google Chrome
...
Chrome:
console._commandLineAPI.clear();
Safari:
console._inspectorCommandLineAPI.clear();
You can create your own variable, which works in both:
if (typeof console._commandLineAPI !== 'undefined') {
console.API = console._commandL...
What are Flask Blueprints, exactly?
...laster of your application.
# An example
from flask import Blueprint
tree_mold = Blueprint("mold", __name__)
@tree_mold.route("/leaves")
def leaves():
return "This tree has leaves"
@tree_mold.route("/roots")
def roots():
return "And roots as well"
@tree_mold.route("/rings")
@tree_mold.r...