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How to avoid isset() and empty()
...of "xyz is undefined" and "undefined offset" messages when running on the E_NOTICE error level, because the existence of variables is not explicitly checked using isset() and consorts.
...
Will using 'var' affect performance?
...it ([0] string string1,
[1] string string2)
IL_0000: nop
IL_0001: ldc.i4.s 9
IL_0003: newarr [mscorlib]System.Char
IL_0008: newobj instance void [mscorlib]System.String::.ctor(char[])
IL_000d: stloc.0
IL_00...
Difference between JSON.stringify and JSON.parse
...pt object into JSON text and stores that JSON text in a string, eg:
var my_object = { key_1: "some text", key_2: true, key_3: 5 };
var object_as_string = JSON.stringify(my_object);
// "{"key_1":"some text","key_2":true,"key_3":5}"
typeof(object_as_string);
// "string"
JSON.parse turns a...
Best practices with STDIN in Ruby?
...ual file that gets all input from named files or all from STDIN.
ARGF.each_with_index do |line, idx|
print ARGF.filename, ":", idx, ";", line
end
# print all the lines in every file passed via command line that contains login
ARGF.each do |line|
puts line if line =~ /login/
end
Thank goo...
How to get error message when ifstream open fails
...ilure:
std::ifstream f;
//prepare f to throw if failbit gets set
std::ios_base::iostate exceptionMask = f.exceptions() | std::ios::failbit;
f.exceptions(exceptionMask);
try {
f.open(fileName);
}
catch (std::ios_base::failure& e) {
std::cerr << e.what() << '\n';
}
e.what(), ho...
Making a UITableView scroll when text field is selected
...
The simplest solution for Swift 3, based on Bartłomiej Semańczyk solution:
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(CreateEditRitualViewController.keyboardWillShow(notificati...
What does an underscore in front of an import statement mean?
...ort is used for the side-effect of registering the sqlite3 driver as a database driver in the init() function, without importing any other functions:
sql.Register("sqlite3", &SQLiteDriver{})
Once it's registered in this way, sqlite3 can be used with the standard library's sql interface in your ...
Temporarily disable auto_now / auto_now_add
...s:
# my model
class FooBar(models.Model):
title = models.CharField(max_length=255)
updated_at = models.DateTimeField(auto_now=True, auto_now_add=True)
# my tests
foo = FooBar.objects.get(pk=1)
# force a timestamp
lastweek = datetime.datetime.now() - datetime.timedelta(days=7)
FooBar.obj...
Checking for empty queryset in Django
...is the code I refer to is only an example that it contains a line if not my_objects: to demonstrate that this is how they do it in the docs. All else is utterly irrelevant so I do not get your point. They could as well make a thousand queries and it would still be totally irrelevant as this is not t...
Preferred way to create a Scala list
...
That is, you can now work on that IndexedSeq:
scala> list.foldLeft(0)(_+_)
res0: Int = 55
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