Dynamic Typing is a property of a programming language where type checks are performed mostly at run time.

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Developing a dynamic language

I have created several hand written compilers for very simple languages but now I want to try my hand at developing a dynamic language, similar to a simplified Python or Ruby. However, it was easy ...
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How to avoid typical “dynamic language mistakes”?

I've recently poured a couple of hours into JavaScript because I wanted to benefit from the massive userbase. Doing that I have noticed a pattern that most people attribute to dynamic languages. You ...
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How is static typing really helpful in bigger projects?

While curiosing on the main page of a scripting programming language's site, I encountered this passage: When a system gets too big to keep in your head, you can add static types. This made me ...
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What semantic features of Python (and other dynamic languages) contribute to its slowness?

I don't know very well Python. I'm trying to understand more precisely what exact features of dynamic languages (à la Python, Lua, Scheme, Perl, Ruby, ....) are forcing their implementations to be ...
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Gradual Typing: “Almost every language with a static type system also has a dynamic type system”

This claim by Aleks Bromfield states: Almost every language with a static type system also has a dynamic type system. Aside from C, I can't think of an exception Is this a valid claim? I ...
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Why generic interface cannot implement dynamic type?

If it possible: IList <dynamic> = new List <dynamic>; or: class A <T> { A(T){} } class B: A <dynamic> {} . Why it is not possible to do this: class U: IEnumerable <...
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Are dynamic languages at disadvantage for agile development?

From what I've read agile development often involves refactoring or reverse engineering code into diagrams. Of course there is much more than that, but if we consider the practices that rely on these ...
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What can I use instead of Interfaces in Ruby (or any other dynamic language)?

My goal is to define contracts between classes. I like duck typing and all but I'd like also to define an interface between different layers of my application to clearly define which are the method ...
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in dynamic language like javascript how do you know what the argument is?

In Java or Scala if I have an argument configuration: Conf, I can look for Conf class/trait/case class and see its construct so I know which arguments to pass. Recently I started dealing with ...
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Generating a class dynamically from types that are fetched at runtime

Is it possible to do the following in C# (or in any other language)? I am fetching data from a database. At run time I can compute the number of columns and data types of the columns fetched. Next I ...
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Do dynamically typed languages, such as Ruby and JavaScript, do any dynamic type checking?

If we look at the definition of "dynamically-typed programming languages" in Wikipedia, it says: Programming languages which include dynamic type-checking but not static type-checking are often ...
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How and when did it happen that, a type is an interface?

I came from a highly functional and procedural background in programming, and never knew that a type is the same as an interface. As in the Design Patterns book by GoF, it says: A type is a name ...
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Confusion about data types, compilers, hardware data representation and static vs dynamic typing [closed]

I am trying to understand static vs dynamic typing, but am really struggling to see how everything fits together. It all starts with data types. As far as I understand, data types are quite abstract ...
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9answers
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What is the supposed productivity gain of dynamic typing? [closed]

I often heard the claim that dynamically typed languages are more productive than statically typed languages. What are the reasons for this claim? Isn't it just tooling with modern concepts like ...
2
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1answer
169 views

Type checking as opposed to multiple functions?

In statically-typed languages such as Java, code such as the following is common (not much of a realistic example, I know): public String flip(String text) { String result = ""; for (int i = ...
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1answer
75 views

Methodology for exploring APIs in dynamic languages

As a regular user of Standard ML and, to a lesser extent, Haskell, the following pattern is deeply ingrained into my "instinctive" approach to navigating and learning new APIs: Understand the types. ...
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22answers
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Is type safety worth the trade-offs?

I began coding in in Python primarily where there is no type safety, then moved to C# and Java where there is. I found that I could work a bit more quickly and with less headaches in Python, but then ...
13
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2answers
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Is an Optional/Maybe type useful in dynamic languages?

Optional is useful in an obvious way in a statically typed language, but I'm wondering if it's also useful in dynamic languages. Usually there's no compiler telling you, "hey, you used this Optional&...
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Can static and dynamically typed languages be seen as different tools for different types of jobs?

Yes, similar questions have been asked but always with the aim of finding out 'which one is better.' I'm asking because I came up as a dev primarily in JavaScript and don't really have any extensive ...
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Does this code follow duck typing?

The principle of duck typing says that you shouldn't care what type of object you have - just whether or not you can do the required action with your object. For this reason the isinstance keyword is ...
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1answer
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With sufficiently advanced static typing, what are the advantages of dynamic type systems? [closed]

This question appears to be fairly well tread, for example: Do dynamic typed languages deserve all the criticism? What is the supposed productivity gain of dynamic typing? etc. However, most ...
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2answers
173 views

What is the best type to represent a number in java and why? [closed]

I am developing a dynamically typed, interpreted programming language, which is interpreted by a runtime written in Java. As Java is statically typed, I need to define how the numbers used in the ...
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10answers
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Why dynamically typed languages do not let the developer specify the type?

The dynamically typed languages I know never let the developers specify the types of variables, or at least have a very limited support for that. JavaScript, for example, doesn't provide any ...
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How can a statically typed language support duck typing?

I understand what dynamic and static type systems are, and what duck typing is. But I don't understand how you can have a static language that supports duck typing. To my understanding only a ...
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5answers
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Is there a correlation between the scale of the project and the strictness of the language?

Explaining the difference between strictness of languages and paradigms to a colleague of mine, I ended up asserting that: Tolerant languages, such as dynamic and interpreted languages, are used ...
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7answers
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What functionality does dynamic typing allow? [closed]

I've been using python for a few days now and I think I understand the difference between dynamic and static typing. What I don't understand is under what circumstances it would be preferred. It is ...
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2answers
345 views

What's the benefit of having everything as an object in dynamically typed programming language? [closed]

modern dynamic programming languages like Python, Ruby and Javascript all take the approach of treating everything as an object, what's the benefit of this approach, and what's the curse of it? ...
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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 ...
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Are there programming languages that support both static and dynamic typing? [duplicate]

Being either static or dynamic should be something completely supported in the language. Static vs dynamic shouldn't be something that you have to turn on and off, switching between basically 2 ...
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2answers
561 views

C# static practices coming from dynamic background

I have been dappling in C# after coming from several years in PHP. I don't find the language particularly difficult, although there are considerably more constructs for me to get used to. My question ...
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Is it a bad idea to return different data types from a single function in a dynamically typed language?

My primary language is statically typed (Java). In Java, you have to return a single type from every method. For example, you can't have a method that conditionally returns a String or conditionally ...
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3answers
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Is it possible to have a dynamically typed language without duck typing? [closed]

This question has been asked here, but received poor answers and didn't clarify the issue. I believe it justifies asking it again. I understand that you can have duck typing with either dynamically ...
0
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1answer
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Is there a way to prevent variables from changing their type in Python?

It is useful to have the interpreter derive the type of a variable automatically. This on its own is similar to the auto keyword in C++11. However, in Python variables can change their type after ...
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When to not use dynamic in C# [closed]

I'm making a class similar to the following: public class KeyValue { public readonly string key; public readonly object value; } Value could be of any object type as a result of this design....
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9answers
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Dynamic vs Statically typed languages for websites [closed]

This statement suggests that statically typed languages are not ideal for web sites: I’ll contrast that with building a website. When rendering web pages, often you have very many components ...
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Are design patterns independent of programming languages?

I have been recently working on Objective C and came across use of Delegate pattern. I had seen most of the common patterns theoretically in Java, thanks to the Head First book. But at times looking ...
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1answer
861 views

Static typing vs. dynamic typing [closed]

I'm developing my own programming language in my spare time as a hobby. It's an interpreted language. Currently the syntax for variables is this: %<variable> = <value> Here are some ...
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1answer
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A question about static types

How would you statically type the following JavaScript program function c(str) { c = eval(str); return c(str); } I'm not trying to start a flame war but I'm genuinely curious. I've always ...
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Is there a real advantage to dynamic languages? [closed]

First I want to say Java is the only language I ever used, so please excuse my ignorance on this subject. Dynamically typed languages allow you to put any value in any variable. So for example you ...
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2answers
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is JS a gradually typed language?

I was researching on statically typed and dynamically typed concepts and found out there is another type system called gradually typed. From wikipedia Gradual typing is a type system in which ...
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4answers
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Architectural differences between dynamic and static languages

Are there any major architectural differences when designing applications that will be built on static languages (such as C# or Java) and dynamic languages (such as Ruby or Python)? Which are the ...
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0answers
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How significant is the impact of the type system (static/dynamic) on the overall design of programs? [duplicate]

Coming from Java, I've never used a language with dynamic typing. I'm very used to the static-typing way of thinking. My question is, how much does the use of dynamic typing as opposed to static ...
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6answers
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What is better for prototyping: a statically-typed language, or a dynamically-typed one? [closed]

When working out the design for a new system, is it better to start with a statically-typed language (like Haskell), or a dynamically-typed language (like Ruby)? Arguments I can think of: With a ...
3
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6answers
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In Java, would you sacrifice type safety for a nicer programming interface

When and why would you generally sacrifice typesafety for a nicer programming interface? Let me give you an example: if you had the choice between two event aggregators, which one would you prefer ...
4
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3answers
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Classes in OOP , methods and attributes memory internals [closed]

I would assume that instances of the same class would actually share their methods, and just have save different attributes in their namespace. How often do you arbitrary add methods to a single ...
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3answers
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How do statically typed languages handle test discovery? [closed]

I come from a Python background, so I'm used to pretty automatic test discovery. For example, the py.test library automatically locates any files which begin with test, finds classes whose names start ...
4
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1answer
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How are atomic operations are a dynamic language feature?

I was told that atomic operations are a dynamic language feature. I was too afraid to ask in that context what this actually means because I didn't want my coworkers to think I'm stupid. But I ...
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6answers
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Why is PHP's method of comparing different types bad?

I'm working on designing a new programming language and trying to decide how I will do variable comparisons. Along with many different types of languages, I've used PHP for years and personally had ...
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2answers
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Are all scripting languages dynamically typed? [closed]

Are all scripting languages dynamically typed? I am using TCL. It is a scripting language and it does not enforce or allow type delaration of variables. It is instead a dynamically-typed language ...
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Is changing the type of a variable partway through a procedure in a dynamically typed language bad style?

In Python (and occasionally PHP) where variables do not have fixed types, I'll frequently perform 'type transformations' on a variable part-way through my code's logic. I'm not (necessarily) talking ...