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Rails: Logging the entire stack trace of an exception
.... While the logger itself is thread safe. Usually I join my message in one string then log it.
– Morozov
Dec 15 '15 at 10:31
...
What does auto&& tell us?
... deep copy.
This allows you to have something like:
std::vector<std::string> foo();
So:
auto var = foo();
will perform a copy of the returned vector (expensive), but:
auto &&var = foo();
will swap the internal representation of the vector (the vector from foo and the empty v...
Subscripts in plots in R
...
And if you want the subscript to be a string, just put it in quotes: plot(1:10, xlab=expression('hi'[5]*'there'[6]^8*'you'['down here']*'and'^'up'*'there'))
– Stewart Macdonald
Sep 11 '14 at 7:28
...
C# switch statement limitations - why?
...t believe the compiler generates constant-time branching when switching on strings either.
– Drew Noakes
Dec 3 '10 at 21:29
...
What is the easiest way to remove the first character from a string?
...rate one more suggested answer:
require 'benchmark'
N = 1_000_000
class String
def eat!(how_many = 1)
self.replace self[how_many..-1]
end
def first(how_many = 1)
self[0...how_many]
end
def shift(how_many = 1)
shifted = first(how_many)
self.replace self[how_many..-1]
...
Python truncate a long string
How does one truncate a string to 75 characters in Python?
17 Answers
17
...
How to convert date to timestamp in PHP?
...:i:s', '22-09-2008 00:00:00');
if ($d === false) {
die("Incorrect date string");
} else {
echo $d->getTimestamp();
}
1222093324 (This will differ depending on your server time zone...)
If you want to specify in which time zone, here EST. (Same as New York.)
$d = DateTime::createFrom...
How to change Hash values?
...def convert_hash hash
hash.inject({}) do |h,(k,v)|
if v.kind_of? String
h[k] = to_utf8(v)
else
h[k] = convert_hash(v)
end
h
end
end
# Iconv UTF-8 helper
# Converts strings into valid UTF-8
#
# @param [String] untrusted_string the ...
C# Java HashMap equivalent
...xer. It goes like this :
public class NullableDictionnary : Dictionary<string, string>
{
string null_value;
public StringDictionary this[string key]
{
get
{
if (key == null)
{
return null_value;
}
re...
C# How can I check if a URL exists/is valid?
...nt()) {
client.HeadOnly = true;
// fine, no content downloaded
string s1 = client.DownloadString("http://google.com");
// throws 404
string s2 = client.DownloadString("http://google.com/silly");
}
You would try/catch around the DownloadString to check for errors; no error? It e...