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Different ways of clearing lists
..., 3]
>>> b = a
>>> del a[:] # equivalent to del a[0:len(a)]
>>> print(a)
[]
>>> print(b)
[]
>>> a is b
True
You could also do:
>>> a[:] = []
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How can I get query string values in JavaScript?
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Update: Sep-2018
You can use URLSearchParams which is simple and has decent (but not complete) browser support.
const urlParams = new URLSearchParams(window.location.search);
const myParam = urlParams.get('myParam');
PS
Unfortunately URL...
cannot load such file — bundler/setup (LoadError)
I'm setting Rails 4 application with Ruby 2.0, but I'm getting "Web application could not be started" and get this trace:
1...
How do I get the width and height of a HTML5 canvas?
... and height attributes are not present in the canvas element, the default 300x150 size will be returned. To dynamically get the correct width and height use the following code:
const canvasW = canvas.getBoundingClientRect().width;
const canvasH = canvas.getBoundingClientRect().height;
Or using th...
How to read the output from git diff?
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Lets take a look at example advanced diff from git history (in commit 1088261f in git.git repository):
diff --git a/builtin-http-fetch.c b/http-fetch.c
similarity index 95%
rename from builtin-http-fetch.c
rename to http-fetch.c
index f3e63d7..e8f44ba 100644
--- a/builtin-http-fetch.c
+++ b/htt...
Preferred method to store PHP arrays (json_encode vs serialize)
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20 Answers
20
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Check if string begins with something? [duplicate]
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Use stringObject.substring
if (pathname.substring(0, 6) == "/sub/1") {
// ...
}
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Declaration/definition of variables locations in ObjectiveC?
...properties can be declared.
Before "modern" Objective-C (in "old" Obj-C 2.0) you didn't have a lot of choices. Instance variables used to be declared in the header between the curly brackets { }:
// MyClass.h
@interface MyClass : NSObject {
int myVar;
}
@end
You were able to access these var...
Check if a string has white space
...e input string:
function hasWhiteSpace(s) {
return s.indexOf(' ') >= 0;
}
Or you can use the test method, on a simple RegEx:
function hasWhiteSpace(s) {
return /\s/g.test(s);
}
This will also check for other white space characters like Tab.
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How to use base class's constructors and assignment operator in C++?
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edited Dec 1 '09 at 7:22
answered Aug 4 '09 at 11:32
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