Questions involving the design and structure of programming languages.

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1answer
68 views

Why is Throwable initCause designed to be called only once?

I find it really odd that the initCause method of Java's Throwable class can only be called once, or even not at all (if the constructor accepting a Throwable was used). This makes exception chaining ...
1
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0answers
125 views

What is the logic behind the use of different arrows (-> <-) in Haskell?

I've been thinking about language design lately, and reading over some of the new things in Haskell (always a nice source of inspiration). I'm struck by the many odd uses of the left <- and right ...
4
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1answer
102 views

Is there a better alternative than abusing the IDisposable pattern?

Consider the following (Microsoft-sanctioned) code: <% using (Html.Form<HomeController>(action=>action.Index())) { %> <input type="text" id="search" /> <input ...
-1
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1answer
261 views

Are there any scenarios where the 'Dispose Pattern' shouldn't be used on an Object which contains managed and un-managed resources?

MSDN says that to properly clean up an object which contains managed and un-managed resources, you need to implement the 'Dispose Pattern'. Given that the class implements the IDisposable interface, ...
4
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4answers
566 views

How does Python compile some its code in C?

I read that some constructs of Python are more efficient because they are compiled in C. https://wiki.python.org/moin/PythonSpeed/PerformanceTips Some of the examples used were map() and filter(). I ...
1
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3answers
65 views

Property-level value transformation for indirect object casting

Does any programming language exist to support the explicit, property-level object copy? For example, assume this code: public class Student { public string Name { get; set; } public ...
2
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1answer
182 views

How do you make decorators as powerful as macros?

Quick background: I am designing a Pythonic language that I want to be as powerful as Lisp while remaining easy to use. And by "powerful", I mean "flexible and expressive". I've just been introduced ...
3
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5answers
853 views

Does this kind of programming language exist?

I'm thinking about creating my own pet programming language, and I have been wondering if similar language already exists. The basic idea is that the language itself would be dynamically typed with ...
6
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7answers
687 views

Why isn't there a next operation on enums?

In most popular programming languages like Java and C# there is a way to define enums, which are essentially datatypes with a fixed set of values, e.g. DayOfWeek. The problem is, given a value, e.g. ...
3
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3answers
464 views

Functional programming strategies in imperative languages

I've been convinced for awhile now that some strategies in functional programming are better suited to a number of computations (i.e immutability of data structures). However, due to the popularity of ...
41
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7answers
3k views

Why is the finalize method included in Java?

According to this post, we should never rely on the finalize method to be called. So why did Java include it in the programming language at all? It seems like a terrible decision to include in any ...
8
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3answers
928 views

Is duplicate syntax for defining named functions a bad language design decision?

I am modelling a programming language for fun, and the syntax is heavily influenced by Scala - specifically function definitions. I have encountered a design problem because my language does not ...
40
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5answers
6k views

Why was C# made with “new” and “virtual+override” keywords unlike Java?

In Java there are no virtual, new, override keywords for method definition. So the working of a method is easy to understand. Cause if DerivedClass extends BaseClass and has a method with same name ...
2
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5answers
457 views

Should sanity be a property of a programmer or a program? [closed]

I design and implement languages, that can range from object notations to markup languages. In many cases I have considered restrictions in favor of sanity (common knowledge), like in the case of ...
0
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2answers
444 views

Why doesn't Ruby have implicit conversion of Fixnum into String?

Ruby normally makes things easy. However, it doesn't allow implicitely converting a number to a string: 2.0.0p247 :010 > "a"+1 TypeError: no implicit conversion of Fixnum into String Why is this ...
0
votes
2answers
167 views

Benefits of Java in education? [closed]

I hope this isn't too off-topic and/or opinion based. I'm looking for examples and reasons why Java is an acceptable language for education purposes. Here's why: I learned programming on my own in C ...
5
votes
4answers
543 views

Why do arrays in Java not override equals()?

I was working with a HashSet the other day, which has this written in the spec: [add()] adds the specified element e to this set if this set contains no element e2 such that (e==null ? e2==null : ...
3
votes
6answers
298 views

Do you have to have boxing of primitives in OO language?

Is boxing of primitives required in OO languages to keep them consistent with the rest of the object system (generics etc.)? Or is it avoidable - is it possible to avoid any additional performance ...
31
votes
10answers
7k views

If null is bad, why do modern languages implement it? [closed]

I'm sure designers of languages like Java or C# knew issues related to existence of null references (see Are null references really a bad thing?). Also implementing an option type isn't really much ...
9
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12answers
2k views

Why don't more languages have the ability to compare a value to more than one other value? [closed]

Consider the following: if(a == b or c) In most languages, this would need to be written as: if(a == b or a == c) which is slightly cumbersome and repeats information. I know my above sample ...
17
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5answers
1k views

Why is studying an lisp interpreter in lisp so important?

I have seen many CS curriculums and learning suggestions for new programmers that call for the aspiring programmer to study a lisp interpreter that is specifically written in lisp. All these sites ...
9
votes
2answers
441 views

Why is there a new() constraint in C# but no other similar constraint?

In C# generics, we can declare a constraint for a type parameter T to have a default constructor, by saying where T : new(). However, no other kinds of constraints like this are valid - new(string) ...
2
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2answers
227 views

Are multi-line comments a critical facility in a modern language?

I'm trying to convince the designers of a language that multi-line comments with an arbitrary start and end are important, and should be included. Currently there is only a "comment-to-end-of-line" ...
0
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2answers
72 views

Storing tokens during lexing stage

I am currently implementing a lexer that breaks XML files up into tokens, I'm considering ways of passing the tokens onto a parser to create a more useful data structure out of said tokens - my ...
1
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2answers
204 views

What's the reason of choosing PascalCasing over camelCasing or vice versa from a programming language design POV?

I like both but I notice languages that use camelCasing for members sometimes need more adjustments when you want to edit your code. For example (in Python): node.customData() vs ...
1
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2answers
268 views

Go-like interfaces + multi-methods make sense?

Thinking about the design of a potential new language, I wonder how related are the concepts of built a OO similar to GO interfaces and multi-methods (I get this from ...
4
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3answers
239 views

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 ...
0
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1answer
109 views

Derivations in BNF

I get how to do a derivation of a BNF. My text books do a good job of explaining it (much better than the on-line lecture notes of many profs etc). Example below then my questions: <program> ...
1
vote
3answers
379 views

Why did the Sun engineers decided to make Java only call by value? [closed]

Is there any specific reason they decided to go with Call by value? Is it for simplicity?
26
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7answers
2k views

Disadvantages of scoped-based memory management

I really like scope-based memory management (SBMM), or RAII, as it is more commonly (confusingly?) referred to by the C++ community. As far as I know, except for C++ (and C), there's no other ...
10
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4answers
1k views

Why do all <algorithm> functions take only ranges, not containers?

There are many useful functions in <algorithm>, but all of them operate on "sequences" - pairs of iterators. E.g., if I have a container and like to run std::accumulate on it, I need to write: ...
11
votes
4answers
711 views

What are the problems of bringing C++-like const into a language?

I am interested in the idea of C++-like const not that particular execution (like casting away const). Take for example C# -- it lacks C++-like const, and the reason for it is the the usual -- people ...
5
votes
5answers
1k views

What negative consequences can arise from this language design rule?

Clarification: the rule is meant to prevent accessing variables that are not declared yet. Clarification 2: the rule mandates that the compiler follows calls to functions which are defined in the ...
5
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3answers
408 views

Is there a web-specific reason for the design choices behind the JavaScript language?

With the advent of "the web is the platform", JavaScript is fast becoming the most widely used programming language in the world. However, many tasks that are easy to accomplish in other modern ...
2
votes
3answers
784 views

What are the advantages of pass by value?

I always thought pass by value is a legacy from the early languages, because the designers had never seen anything else. But after seeing the brand new languages like Go adapting the same principle ...
1
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1answer
99 views

If a variable containing a function gave the function's return instead of a reference to the function, what would an array of functions return? [closed]

I'm creating a prototype scripting language similar to something like Javascript. In my language, every single reference to a variable is actually a function call (a getter function), whether it has ...
5
votes
2answers
191 views

Language that embraces mutable state? [closed]

There seems to be a trend towards immutable objects, and pure functional programming. While I recognize the benefits, I find it hard to apply these principles to GUI programming, for example. But I ...
3
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1answer
323 views

Is there a name for the 'break n' construct?

In a conversation earlier this week I was discussing certain language features, and I realized I don't have a good word / phrase to describe a particular feature. Some languages, such as PHP, have a ...
2
votes
6answers
777 views

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 ...
10
votes
6answers
2k views

Are there any ultra high level languages out there? [closed]

Historically a HLL is something like C, Fortran or Pascal and a VHLL is something like Ruby or Python. I am familiar with the terms 4GL, 5GL, DSL and LOP, and those who aren't should read Wikipedia ...
6
votes
3answers
298 views

Clarification about Grammars , Lexers and Parsers

Background info (May Skip): I am working on a task we have been set at uni in which we have to design a grammar for a DSL we have been provided with. The grammar must be in BNF or EBNF. As well as ...
4
votes
5answers
1k views

Programming Languages “Higher Level” Than Python [closed]

In general, I have been presented with these sorts of heirarchies for programming language abstraction: Assembly < C < C++ < Java < Python where C abstracts less than C++ and so on. You ...
5
votes
5answers
2k views

why no native compiler of C# or other “productive” language? [closed]

I've been reading about D and Go and how they aim at being compiled to machine code yet be convenient (like garbage collection, no need to manipulate pointers unless needed) and I agree that there is ...
2
votes
1answer
400 views

Reasoning behind the syntax of octal notation in Java?

Java has the following syntax for different bases: int x1 = 0b0101; //binary int x2 = 06; //octal int x3 = 0xff; //hexadecimal Is there any reasoning on why it is 0 instead of something like ...
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votes
2answers
117 views

What are some examples of inverted classical inheritance? [closed]

Are there any examples of inheritance in languages where classes call their subclasses' methods rather than their super classes' methods? It should not behave like traditional inheritance like the ...
25
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9answers
1k views

Why most “well-known” imperative/OO languages allow unchecked access to types that can represent a 'nothing' value?

I have been reading about the (un)convenience of having null instead of (for example) Maybe. After reading this article, I am convinced that it would be much better to use Maybe (or something ...
33
votes
3answers
1k views

Does Java development typically involve more subclassing than C#/.NET?

I've recently started looking at Android development. This has brought me back into the world of Java software development. The last time I worked with Java, I'll admit, I didn't understand OOP nearly ...
5
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4answers
799 views

Is there a math theory or a model behind programming languages design

I'm trying to understand if a programming languages design is built on some a theoretical model. I came across few links that was describing Programming Language Theory, Lambda Calculus, Formal ...
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5answers
303 views

In retrospect, has it been a good idea to use three-valued logic for SQL NULL comparisons?

In SQL, NULL means "unknown value". Thus, every comparison with NULL yields NULL (unknown) rather than TRUE or FALSE. From a conceptional point of view, this three-valued logic makes sense. From a ...
6
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1answer
467 views

Why appending to a list in Scala should have O(n) time complexity?

I am learning Scala at the moment and I just read that the execution time of the append operation for a list (:+) grows linearly with the size of the list. Appending to a list seems like a pretty ...