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A semantics for Bash scripts?
...ion.
$ foo() { echo $x; }
$ bar() { local x; echo $x; }
$ foo
$ bar
$ x=123
$ foo
123
$ bar
$ …
Environment and process "scope"
Subshells inherit the variables of their parent shells, but other kinds of processes don't inherit unexported names.
$ x=123
$ ( echo $x )
123
$ bash -c 'echo $x'...
Why does PHP consider 0 to be equal to a string?
...alse.
But what if I do need to compare numbers as strings with numbers?
"123" === 123
evaluates false because the left and right term are of different type.
What is actually needed is a weak comparison without the pitfalls of PHP type juggling.
The solution is to explicit promote the terms to ...
array_push() with key value pair
...
Warning: $a['123'] = 456; - string '123' is converted to integer key 123.
– bancer
Jul 2 at 12:58
1
...
Check whether variable is number or string in JavaScript
...constructors, you can use typeof:.
typeof "Hello World"; // string
typeof 123; // number
If you're creating numbers and strings via a constructor, such as var foo = new String("foo"), you should keep in mind that typeof may return object for foo.
Perhaps a more foolproof method of che...
jQuery document.createElement equivalent?
...lease notice that a is a jQuery object while b is a html element:
a.html('123')
// [<div>123</div>]
b.html('123')
// TypeError: Object [object HTMLDivElement] has no method 'html'
$(b).html('123')
// [<div>123</div>]
...
How can I remove all text after a character in bash?
...
@kp123: It's the first example in my answer. The second time I show it (where "tomorrow" is removed), it's almost exactly the situation you're asking about.
– Paused until further notice.
A...
Where to store global constants in an iOS application?
...
You could also do a
#define kBaseURL @"http://192.168.0.123/"
in a "constants" header file, say constants.h. Then do
#include "constants.h"
at the top of every file where you need this constant.
This way, you can switch between servers depending on compiler flags, as in:
#i...
Regular expression for floating point numbers
...g a floating point number is
[+-]?([0-9]*[.])?[0-9]+
This will match:
123
123.456
.456
See a working example
If you also want to match 123. (a period with no decimal part), then you'll need a slightly longer expression:
[+-]?([0-9]+([.][0-9]*)?|[.][0-9]+)
See pkeller's answer for a fuller...
Unable to set data attribute using jQuery Data() API
...('#changeData').click(function() {
$('#foo').data('helptext', 'Testing 123');
// $('#foo').attr('data-helptext', 'Testing 123');
console.log($('#foo').data('data-helptext'));
return false;
});
See demo
Using the Chrome DevTools Console to inspect the DOM, the $('#foo').data('helptext...
How to determine a Python variable's type?
...
Use the type() builtin function:
>>> i = 123
>>> type(i)
<type 'int'>
>>> type(i) is int
True
>>> i = 123.456
>>> type(i)
<type 'float'>
>>> type(i) is float
True
To check if a variable is of a given type, u...