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Using braces with dynamic variable names in PHP
...rom phpNET manual php.net/manual/ru/language.variables.variable.php $price_for_monday = 10; $price_for_tuesday = 20; $today = 'tuesday'; $price_for_today = ${ 'price_for_' . $today}; echo $price_for_today; // will return 20
– Vladimir Ch
Apr 20 '18 at 21:08
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What is the difference between require_relative and require in Ruby?
What is the difference between require_relative and require in Ruby?
7 Answers
7
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How to Customize a Progress Bar In Android
I am working on an app in which I want to show a ProgressBar , but I want to replace the default Android ProgressBar .
9 ...
Javascript “this” pointer within nested function
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@Arashsoft this in this.doSomeEffects() points to std_obj. As explained in the answer above if a function doesn't have object reference then it takes this to be a window object.
– Shivam
Jun 28 '19 at 18:46
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Evenly space multiple views within a container view
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So my approach allows you to do this in interface builder. What you do is create 'spacer views' that you have set to match heights equally. Then add top and bottom constraints to the labels (see the screenshot).
More specifica...
Convert hyphens to camel case (camelCase)
...and have it included in your project.
var str = 'my-hyphen-string';
str = _.camelCase(str);
// results in 'myHyphenString'
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Update multiple rows in same query using PostgreSQL
... one column, it's much more generalizable:
update test as t set
column_a = c.column_a
from (values
('123', 1),
('345', 2)
) as c(column_b, column_a)
where c.column_b = t.column_b;
You can add as many columns as you like:
update test as t set
column_a = c.column_a,
column_c...
How can I check for Python version in a program that uses new language features?
...oesn't have ternary
Also, with is available in Python 2.5, just add from __future__ import with_statement.
EDIT: to get control early enough, you could split it into different .py files and check compatibility in the main file before importing (e.g. in __init__.py in a package):
# __init__.py
#...
Is there a difference between “==” and “is”?
... most cases this logic is true, but it relies on the implementation of the __eq__ special method. As the docs say,
The default behavior for equality comparison (== and !=) is based on
the identity of the objects. Hence, equality comparison of instances
with the same identity results in equa...
Test if a variable is a list or tuple
...
How about: hasattr(a, "__iter__") ?
It tells if the object returned can be iterated over as a generator. By default, tuples and lists can, but not the string types.
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