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JavaScript: client-side vs. server-side validation
...k to the average user. For example, if they enter an invalid email address and move to the next field, you can show an error message immediately. That way the user can correct every field before they submit the form.
If you only validate on the server, they have to submit the form, get an error mes...
What is PECS (Producer Extends Consumer Super)?
I came across PECS (short for Producer extends and Consumer super ) while reading up on generics.
14 Answers
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Set cellpadding and cellspacing in CSS?
In an HTML table, the cellpadding and cellspacing can be set like this:
28 Answers
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What are dictionary view objects?
...sentially what their name says: views are simply like a window on the keys and values (or items) of a dictionary. Here is an excerpt from the official documentation for Python 3:
>>> dishes = {'eggs': 2, 'sausage': 1, 'bacon': 1, 'spam': 500}
>>> keys = dishes.keys()
>>>...
Scala type programming resources
... time. I will try to draw parallels between programming at the value-level and programming at the type-level.
Paradigms
There are two main paradigms in type-level programming: "object-oriented" and "functional". Most examples linked to from here follow the object-oriented paradigm.
A good, fairly...
To underscore or to not to underscore, that is the question
...nguages? For example since C# is case-sensitive you can call a field "foo" and the public property "Foo" and it works fine.
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In Java, when should I create a checked exception, and when should it be a runtime exception? [dupli
When should I create a checked exception, and when should I make a runtime exception?
14 Answers
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Does C# have extension properties?
...ot seen as valuable enough to be included in the previous versions of C# standard. C# 7 and C# 8.0 have seen this as proposal champion but it wasn't released yet, most of all because even if there is already an implementation, they want to make it right from the start.
But it will ...
There is an ...
How to avoid annoying error “declared and not used”
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That error is here to force you to write better code, and be sure to use everything you declare or import. It makes it easier to read code written by other people (you are always sure that all declared variables will be used), and avoid some possible dead code.
But, if you real...
How do I vertically align text in a div?
...the most effective way to align text with a div. I have tried a few things and none seem to work.
30 Answers
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