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structure vs class in swift language
From Apple book
"One of the most important differences between structures and classes is that structures are always copied when they are passed around in your code, but classes are passed by reference."
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AngularJS : Differences among = & @ in directive scope? [duplicate]
...xplained ... if your directive looks like this:
<my-directive target="foo"/>
Then you have these possibilities for scope:
{ target : '=' }
This will bind scope.target (directive) to $scope.foo (outer scope). This is because = is for two-way binding and when you don't specify anything...
Remove all child elements of a DOM node in JavaScript
...ers may optimize for the case where the value is an empty string).
doFoo.onclick = () => {
const myNode = document.getElementById("foo");
myNode.innerHTML = '';
}
<div id='foo' style="height: 100px; width: 100px; border: 1px solid black;">
<span>Hello</span>
&l...
Difference between “and” and && in Ruby?
...ength, which can lead to peculiar behavior if you're not prepared for it:
foo = :foo
bar = nil
a = foo and bar
# => nil
a
# => :foo
a = foo && bar
# => nil
a
# => nil
a = (foo and bar)
# => nil
a
# => nil
(a = foo) && bar
# => nil
a
# => :foo
The same t...
Command not found error in Bash variable assignment
...
You cannot have spaces around your '=' sign.
When you write:
STR = "foo"
bash tries to run a command named STR with 2 arguments (the strings '=' and 'foo')
When you write:
STR =foo
bash tries to run a command named STR with 1 argument (the string '=foo')
When you write:
STR= foo
bas...
Ruby regular expression using variable name
...n't work, does:
var = "Value"
str = "a test Value"
p str.gsub( /#{var}/, 'foo' ) # => "a test foo"
Things get more interesting if var can contain regular expression meta-characters. If it does and you want those matacharacters to do what they usually do in a regular expression, then the sam...
How to pass command line argument to gnuplot?
I want to use gnuplot to draw figure from data file, say foo.data . Currently, I hardcoded the data file name in the command file, say foo.plt , and run command gnuplot foo.plg to plot data. However, I want to pass the data file name as a command argument, e.g. running command gnuplot foo.plg f...
List vs tuple, when to use each? [duplicate]
In Python, when should you use lists and when tuples?
7 Answers
7
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Run a string as a command within a Bash script
I have a Bash script that builds a string to run as a command
8 Answers
8
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Remove the last line from a file in Bash
I have a file, foo.txt , containing the following lines:
14 Answers
14
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