Questions involving the design and structure of programming languages.

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3
votes
1answer
105 views

Documentation Generation - FiM++

This is a question I originally asked on Stack Overflow, but as a conceptual design question as opposed to a technical issue, I believe it may be more appropriate, or possibly have alternate parallel ...
3
votes
2answers
62 views

Why aren't field-like events implemented as a list of delegates?

tl;dr: Why are field-like events implemented as a single delegate field? Wouldn't it be more straight-forward to use a list of delegates, thereby eliminating the null special case and avoiding all the ...
0
votes
0answers
22 views

Limiting repetitions in Backus Naur forms

Is there a method using Backus-Naur Form (BNF) to limit the number of repetitions? Let's take the description of a decimial number. A decimal number will consist of 1 to many digits. Is there a ...
2
votes
2answers
337 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 ...
5
votes
3answers
560 views

How to make support for bindings for a scripting language

Main I'm making a scripting language using C++. I plan to use it with a simple test game editor. But I have to make a support for bindings to call game engine's nodes' methods to update positions, ...
34
votes
4answers
3k views

Why structs and classes are separate concepts in C#?

While programming in C#, I stumbled upon a strange language design decision that I just can't understand. So, C# (and the CLR) has two aggregate data types: struct (value-type, stored on the stack, ...
3
votes
4answers
491 views

Why are cases in a switch statement not isolated? [duplicate]

As far as I can tell in all C-like languages something like this: switch(variable) { case 'a': printf("Hello "); case 'b': printf("World!"); case 'c': ...
19
votes
5answers
4k views

Why design a modern language without an exception-handling mechanism?

Many modern languages provide rich exception handling features, but Apple's Swift programming language does not provide an exception handling mechanism. Steeped in exceptions as I am, I'm having ...
6
votes
2answers
349 views

Why is the 'out' keyword used in two seemingly disparate contexts?

In C#, the out keyword can be used in two different ways. As a parameter modifier in which an argument is passed by reference class OutExample { static void Method(out int i) { i = ...
1
vote
1answer
85 views

Is unifiing ADTs with typeclasses possible?

When i was thinking about language design i got an idea that ADTs (Aglebraic Data Types) and typeclasses could be the same thing. They can both represent a group of types, but in haskell they are not ...
1
vote
1answer
89 views

Thinking about a language for build definitions

I want to write a little tool that parses build definitions and converts them to a ninja.build file. It should not abstract compilation like CMake or Meson, but be similar to make in that you manually ...
54
votes
11answers
6k views

Did the developers of Java consciously abandon RAII?

As a long-time C# programmer, I have recently come to learn more about the advantages of Resource Acquisition Is Initialization (RAII). In particular, I have discovered that the C# idiom: using (var ...
41
votes
15answers
10k views

How have languages influenced CPU design? [closed]

We are often told that the hardware doesn't care what language a program is written in as it only sees the compiled binary code, however this is not the whole truth. For example, consider the humble ...
29
votes
8answers
3k 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 ...
4
votes
2answers
238 views

Needs (in principle) C++ parenthesis around if statement condition?

In current C++ when body of if statements contain only one command then: Parenthesis around if condition are mandatory but block are optional. So, both examples are OK: if ( condition ) { return 0; ...
34
votes
2answers
8k views

What are 4th & 5th programming language generations? Are there more of them? [closed]

As it is often classified at school/college level, popular programming languages (C#, Java, C++) are all 3rd generation languages (with higher level of abstraction from the machine's physical parts). ...
14
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 ...
9
votes
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 ...
7
votes
1answer
254 views

Do any notable C extensions include integer types whose behavior is independent of machine word size

An interesting characteristic of C compared with some other languages is that many of its data types are based upon the word size of the target architecture, rather than being specified in absolute ...
1
vote
3answers
155 views

Does overriding a method affect a superclass's call?

I'm trying to understand some of the nuances of inheritance but I can't find an answer to this question. Consider the following: class SuperClass { method foo { print "in SuperClass.foo" ...
25
votes
6answers
2k views

What are the caveats of implementing fundamental types (like int) as classes?

When designing and implenting an object-oriented programming language, at some point one must make a choice about implementing fundamental types (like int, float, double or equivalents) as classes or ...
13
votes
5answers
2k views

Why is *declaration* of data and functions necessary in C language, when the definition is written at the end of the source code?

Consider the following "C" code: #include<stdio.h> main() { printf("func:%d",Func_i()); } Func_i() { int i=3; return i; } Func_i() is defined at the end of the source code and ...
52
votes
9answers
39k views

Why use partial classes?

In my understanding, the partial keyword does nothing but allow a class to be split between several source files. Is there any reason to do this other than for code organization? I've seen it used for ...
1
vote
2answers
107 views

What is meant by “redundant, but not duplicative” in the Steelman language requirements?

The Steelman language requirements have this: The language shall require some redundant, but not duplicative, specifications in programs. I think I can see the underlying idea (that re-stating ...
0
votes
1answer
76 views

Is automatic conversion to collection types from non-collection variable a good idea? [closed]

Consider public void Do(string[] aBunchOfStrings) { } or public void Do(IReadOnlyList<string> aBunchOfStrings) { } Would it be a bad idea to allow the function call Do("woei"); resolve ...
2
votes
1answer
395 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 ...
0
votes
0answers
41 views

Rationale behind CSS height with percentage value

I've been using CSS for a few years, but there are some "quirks" that I cannot quite fathom. One of them is the height property when specified with a percentage. To quote the CSS 2.1 Specification ...
5
votes
5answers
3k views

False friends? Keyword “static” in C compared to C++, C# and Java

To me, the use of the keyword static in C and languages like C# and Java are "false friends" like "to become" in English and "bekommen" in German (= "to get" in English), because they mean different ...
0
votes
0answers
58 views

Pre-Compilation Processor:

What I want to do: Parse source code, search for a beginning and closing tag of my own definition (one that does not conflict with any defined patterns in the programming language), and then replace ...
4
votes
7answers
797 views

Why are self-hosting compilers considered a rite of passage for new languages?

I've heard in a number of places now that people expect languages to use, or at least have, a self-hosting compiler in order to deserve respect. I'm curious as to why this is. A compiler seems like a ...
8
votes
4answers
411 views

Use cases for “private” interfaces?

I was wondering if there was a valid use case for being able to properly define the specific internal properties and functions of a class in a way similar to how an interface defines the public ...
42
votes
6answers
8k 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
votes
3answers
643 views

What could be the advantages and disadvantages of decay of Nd arrays to N-level pointers?

I have been thinking of a couple of possible extensions to the C language which I'd like to know the opinion of others about.1 This one is about multi-dimensional arrays. Imagine the following ...
13
votes
4answers
2k 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: ...
9
votes
1answer
1k views

Why does Scala have return but not break and continue

Scala does not have break or continue, so some loop behavior takes a bit more of thinking. Ending a loop early requires tail recursion, exceptions, or scala.util.control.Breaks (which uses ...
43
votes
12answers
10k views

Should I use a parser generator or should I roll my own custom lexer and parser code?

What specific advantages and disadvantages of each way to working on a programming language grammar? Why/When should I roll my own? Why/When should I use a generator?
0
votes
2answers
437 views

What's the advantage of auto-property initializers without primary constructors?

In this chart about the features that are in or out of the next version of Roslyn (specifically, for C#), primary constructors are out, but auto-property initializers are in. The best use case I've ...
0
votes
0answers
124 views

Best way to handle language interoperability

Background In a language like F#, direct interoperability with most other .NET languages is possible. For example, it is possible to use classes written in C# directly in F#, and it is possible to ...
1
vote
2answers
208 views

Why is object-level privacy difficult to use as a paradigm, and why is it desirable?

I have heard a prominent language designer remark that no language today enforces real object privacy, and we are still unsure whether it is possible in practice to design a language that does. ...
7
votes
4answers
911 views

When does it make sense to compile my own language to C code first?

When designing an own programming language, when does it make sense to write a converter that takes the source code and converts it to C or C++ code so that I can use an existing compiler like gcc to ...
35
votes
12answers
4k views

Why do most programming languages have special keyword or syntax for declaring functions? [closed]

Most programming languages (both dynamically and statically typed languages) have special keyword and/or syntax that looks much different than declaring variables for declaring functions. I see ...
0
votes
3answers
148 views

What is the most robust, extensible way to represent a contract in code? [closed]

I would like to find or create a syntax to express business contracts programmatically, and I am looking for a robust, flexible, future-resistant way to do this. A client should be able to add a ...
44
votes
9answers
15k views

Why is String immutable in Java?

I couldn't understand the reason of it. I always use String class like other developers, but when I modify the value of it, I need to create new instance of String. What might be the reason of ...
1
vote
1answer
266 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 ...
4
votes
1answer
131 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
votes
1answer
301 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, ...
79
votes
20answers
13k views

Are null references really a bad thing?

I've heard it said that the inclusion of null references in programming languages is the "billion dollar mistake". But why? Sure, they can cause NullReferenceExceptions, but so what? Any element of ...
4
votes
4answers
1k 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 ...
2
votes
1answer
285 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 ...
37
votes
22answers
3k views

Has whitespace in identifiers ever been idiomatic? [closed]

C# style suggests using CamelCase in identifiers to delimit words. Lisp tradition suggests using-dashes-instead. Has there ever existed a programming language where using spaces in identifiers was ...