a type system is a collection of rules that assign a property called a type to the various constructs—such as variables, expressions, functions or modules— that a computer program is composed of.

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Should we define types for everything?

Recently I got into a problem with the readability of my code. I had a function that did an operation and returned a string representing the ID of this operation for future reference (a bit like ...
54
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6answers
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Dynamically vs Statically typed languages studies

Do there exist studies done on the effectiveness of statically vs dynamically typed languages? In particular: Measurements of programmer productivity Defect Rate Also including the effects of ...
26
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5answers
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What arguments are there in favor of weak typing?

This came up in a discussion with a friend, and I found myself hard-pressed to think up an any good arguments. What benefits do weak typing confer?
24
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8answers
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Using a “strong” type system in the real world, say, for large-scale web-apps?

I know this is a very broad, ambiguous, and possibly philosophical question. To an extent, that the most important keyword in the question - "strong" type system - itself, is ill-defined. So, let me ...
42
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12answers
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When is type testing OK?

Assuming a language with some inherent type safety (e.g., not JavaScript): Given a method that accepts a SuperType, we know that in most cases wherein we might be tempted to perform type testing to ...
32
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7answers
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Is Haskell's type system an obstacle to understanding functional programming? [closed]

I'm studying Haskell for the purpose of understanding functional programming, with the expectation that I'll apply the insight that I gain in other languages (Groovy, Python, JavaScript mainly.) I ...
14
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4answers
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Type systems: nominal vs. structural, explicit vs. implicit

I'm a bit confused about the difference between nominal and structural type systems. Can someone please explain how they differ? From what I understand: Nominal: Type compatibility is based on type ...
14
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3answers
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What is the reason of using an interface versus a generically constrained type

In object-oriented languages that support generic type parameters (also known as class templates, and parametric polymorphism, though of course each name carries different connotations), it is often ...
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2answers
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The Definition of “Strong Type Systems” [closed]

I saw Martin Odersky's "The Trouble with Types" presenstaion. He divided programing-languages in two dimensions in the "Type Systems Landscape" chart; A "Static/Dynamic" dimension and A "Strong/Weak" ...
65
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5answers
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Is Haskell's type system formally equivalent to Java's? [closed]

I realize some things are easier/harder in one language than the other, but I'm only interested in type-related features that are possible in one and impossible/irrelevant in the other. To make it ...
43
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9answers
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What are the safety benefits of a type system?

In JavaScript: The Good Parts by Douglas Crockford, he mentions in his inheritance chapter, The other benefit of classical inheritance is that it includes the specification of a system of types. ...
33
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9answers
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Do dynamic typed languages deserve all the criticism? [closed]

I have read a few articles on Internet about programming language choice in the enterprise. Recently many dynamic typed languages have been popular, i.e. Ruby, Python, PHP and Erlang. But many ...
35
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7answers
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Type casting variables in PHP, what is the practical reason for doing this?

PHP, as most of us know, has weak typing. For those who don't, PHP.net says: PHP does not require (or support) explicit type definition in variable declaration; a variable's type is determined ...
26
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1answer
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Type inference in Java 8

Is the introduction of the new lambda notation (see e.g. this article) in Java 8 going to require some kind of type inference? If so, how will the new type system impact the Java language as a whole?
14
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9answers
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Which statically typed languages support intersection types for function return values?

Initial note: This question got closed after several edits because I lacked the proper terminology to state accurately what I was looking for. Sam Tobin-Hochstadt then posted a comment which made ...
3
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3answers
440 views

Should conditional logic be always coded via type system where possible?

I have a choice. Option 1: public class Sample { bool IsRelevant { get; set; } } Option 2: public class Sample { } public class RelevantSample : Sample { } Is there a clear well-known rule ...
17
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1answer
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Why doesn't Haskell have type-level lambda abstractions?

Are there some theoretical reasons for that (like that the type checking or type inference would become undecidable), or practical reasons (too difficult to implement properly)? Currently, we can ...
7
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2answers
684 views

Values, types, kinds, and…?

We all know what a value is. A type is the type of a value. A kind is (loosely) the type of a type. A type constructs a value; a kind constructs a type. So what is the type of a kind, a thing that ...