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PHP Fatal error: Cannot redeclare class
...
It means you've already created a class.
For instance:
class Foo {}
// some code here
class Foo {}
That second Foo would throw the error.
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Creating PHP class instance with a string
...s();
When using namespaces, supply the fully qualified name:
$class = '\Foo\Bar\MyClass';
$instance = new $class();
Other cool stuff you can do in php are:
Variable variables:
$personCount = 123;
$varname = 'personCount';
echo $$varname; // echo's 123
And variable functions & methods.
...
Disable assertions in Python
...time, ideally with some sort of context manager: assertion is evaluated: foo() and switching assertions off: with skip_assertion(): foo(). The benefit of this being that i dont have to add another flag on the function
– Matthijs
Sep 4 '19 at 21:42
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C# 4 default parameter values: How to assign a default DateTime/object value? [duplicate]
... you can't fake it with attributes.
.method private hidebysig static void foo([opt] int32 x) cil managed
{
.param [1] = int32(5)
.maxstack 8
L_0000: nop
L_0001: ret
}
.method //this is a new method
private hidebysig static //it is private, ???, and static
void foo //it returns...
Is it possible to pass a flag to Gulp to have it run tasks in different ways?
...fore will fail, the next argument-value is what we get.
> gulp watch --foo --bar 1337 -boom "Foo isn't equal to bar."
getArg("--foo") // => true
getArg("--bar") // => "1337"
getArg("-boom") // => "Foo isn't equal to bar."
getArg("--404") // => null
Ok, enough for now... Here's a s...
Append values to a set in Python
...set, it should be added with .add(), not .update().
Say you have a string foo_str whose contents are 'this is a sentence', and you have some set bar_set equal to set().
If you do
bar_set.update(foo_str), the contents of your set will be {'t', 'a', ' ', 'e', 's', 'n', 'h', 'c', 'i'}.
If you do bar...
Latex Remove Spaces Between Items in List
...{enumitem}
\begin{document}
Less space:
\begin{itemize}[noitemsep]
\item foo
\item bar
\item baz
\end{itemize}
Even more compact:
\begin{itemize}[noitemsep,nolistsep]
\item foo
\item bar
\item baz
\end{itemize}
\end{document}
The enumitem package provides a lot of features to custom...
How to create a file in Ruby
...ile.
If the text to be output is a string, rather than write:
File.open('foo.txt', 'w') { |fo| fo.puts "bar" }
or worse:
fo = File.open('foo.txt', 'w')
fo.puts "bar"
fo.close
Use the more succinct write:
File.write('foo.txt', 'bar')
write has modes allowed so we can use 'w', 'a', 'r+' if n...
What is the benefit of using $() instead of backticks in shell scripts?
..."$(echo \\\\a)"
\a \\a
# Note that this is true for *single quotes* too!
$ foo=`echo '\\'`; bar=$(echo '\\'); echo "foo is $foo, bar is $bar"
foo is \, bar is \\
Nested quoting inside $() is far more convenient:
echo "x is $(sed ... <<<"$y")"
instead of:
echo "x is `sed ... <<&l...
Get the data received in a Flask request
... flask import Flask, request, jsonify
app = Flask(__name__)
@app.route('/foo', methods=['POST'])
def foo():
data = request.json
return jsonify(data)
To post JSON with curl:
curl -i -H "Content-Type: application/json" -X POST -d '{"userId":"1", "username": "fizz bizz"}' http://localhost...