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In Java, is there a way to write a string literal without having to escape quotes?
...of resides in the Java Language Specification:
StringLiteral:
"StringCharacters"
StringCharacters:
StringCharacter
| StringCharacters StringCharacter
StringCharacter:
InputCharacter but not " or \
| EscapeSequence
As you can see a StringLiteral can just be bound by " and ca...
How do I use sudo to redirect output to a location I don't have permission to write to?
...ut. The redirection of the output is not performed by sudo.
There are multiple solutions:
Run a shell with sudo and give the command to it by using the -c option:
sudo sh -c 'ls -hal /root/ > /root/test.out'
Create a script with your commands and run that script with sudo:
#!/bin/sh
ls -hal...
Haskell: Lists, Arrays, Vectors, Sequences
...st. The best example of lists screwing up performance tends to come from [Char] which the prelude has aliased as String. Char lists are convient, but tend to run on the order of 20 times slower than C strings, so feel free to use Data.Text or the very fast Data.ByteString. I'm sure there are othe...
Why don't structs support inheritance?
...hat short[] can't be converted to int[] (short of conversion code, like 'a.Select(x => (int) x).ToArray()'). If the runtime disallowed the cast from Base to Derived, it would be a "wart", as that IS allowed for reference types. So we have two different "warts" possible -- forbid struct inherita...
How to determine if a number is a prime with regex?
...nerated has a length equal to the number supplied. So the string has three characters if and only if n == 3.
.?
The first part of the regex says, "any character, zero or one times". So basically, is there zero or one character-- or, per what I mentioned above, n == 0 || n == 1. If we have the mat...
How to find out line-endings in a text file?
...
Unfortunately, I don't think vi can show those specific characters. You can try od -c <filename> which I believe will display \n or \r\n.
– Ryan Berger
Aug 25 '10 at 22:51
...
Is it better to use std::memcpy() or std::copy() in terms to performance?
...in as large of chunks as possible (many other implementations operate with char / char *, whereas I operate with T / T * (where T is the largest type in the user's implementation that has correct overflow behavior), so fast memory access on the largest types I can is central to the performance of my...
What is the difference between Ruby 1.8 and Ruby 1.9
...ow
if statements do not introduce scope in Ruby.
What's changed?
Single character strings.
Ruby 1.9
irb(main):001:0> ?c
=> "c"
Ruby 1.8.6
irb(main):001:0> ?c
=> 99
String index.
Ruby 1.9
irb(main):001:0> "cat"[1]
=> "a"
Ruby 1.8.6
irb(main):001:0> "cat"[1]
=>...
Node.js app can't run on port 80 even though there's no other process blocking the port
... 80 you can redirect port 80 to your application's port (>1024) using
iptables -t nat -I PREROUTING -p tcp --dport 80 -j REDIRECT --to-port 3000
This will work if your application is running on port 3000.
share
...
Check if a string contains a number
...n, like this
>>> def hasNumbers(inputString):
... return any(char.isdigit() for char in inputString)
...
>>> hasNumbers("I own 1 dog")
True
>>> hasNumbers("I own no dog")
False
Alternatively you can use a Regular Expression, like this
>>> import re
>&g...