When comparing Scheme vs Rust, the Slant community recommends Scheme for most people. In the question“What is the best programming language to learn first?” Scheme is ranked 8th while Rust is ranked 21st. The most important reason people chose Scheme is:
Scheme syntax is extremely regular and easy to pick up. A *formal* specification of the syntax fits onto just a few pages; it can be introduced informally in a paragraph or two. Students are not distracted by remembering how to write if statements or loops or even operator precedence because every syntactic follows the same pattern. Ultimately, everything looks something like this: (func a b c) This includes not only user-defined functions but even control flow: (if cond then-clause else-clause) or even primitive operations like `define` and `set`: (define foo 10) (set! foo 11) This means that nothing really has special syntactic treatment in the language. There are essentially no weird edge-cases to memorize, and different concepts are given a more equal weight in the language. (Unlike Algol-like languages which tend to given undue weight to loops and assignment statements, for example.)
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Simple syntax
Scheme syntax is extremely regular and easy to pick up. A formal specification of the syntax fits onto just a few pages; it can be introduced informally in a paragraph or two. Students are not distracted by remembering how to write if statements or loops or even operator precedence because every syntactic follows the same pattern.
Ultimately, everything looks something like this:
(func a b c)
This includes not only user-defined functions but even control flow:
(if cond then-clause else-clause)
or even primitive operations like define
and set
:
(define foo 10)
(set! foo 11)
This means that nothing really has special syntactic treatment in the language. There are essentially no weird edge-cases to memorize, and different concepts are given a more equal weight in the language. (Unlike Algol-like languages which tend to given undue weight to loops and assignment statements, for example.)
Pro No magic - it's clear how everything works
Scheme has far less built into the language itself, helping students see that things like OOP are not magical: they are just patterns for organizing code. Everything in Scheme is built up from a very small set of primitives which compose in a natural and intuitive fashion.
Having a language that does not accord many things special status helps keep students open minded. This will help students later go between different languages and paradigms from procedural to object-oriented to functional.
Pro Great at teaching fundamental programming ideas
Scheme teaches the important, fundamental ideas immediately without the distraction of unnecessary syntax or language features.
Pro Multi platform
GNU/Linux, OS X, and Windows versions available.
Pro Great, well known textbooks
There is a set of very strong textbooks introducing CS and programming using Scheme. These books are available for free online.
The most famous example--and one of the most famous CS books full stop--is Structure and Interpretation of Computer Programs usually known as SICP. This book introduces fundamental ideas in computer science and covers an incredible amount of material quickly and clearly without requiring any prior knowledge.
However, some people find SICP a bit challenging as a first text. Happily, there are other more introductory texts as well. Simply Scheme is a book designed to be read before SICP, easing beginners into the language as well as CS and programming in general. How to Design Programs is another text used in introductory college courses.
Pro Encourages creativity
Pro Robust metaprogramming
The quotation functionality of Lisp allow for extremely powerful, yet syntactically straightforward metaprogramming via macros. This is more powerful than the C preprocessor while being less involved than something like Template Haskell or F# quotations.
Using macros to properly decompose a problem domain teaches new developers good habits, improving composibility and reliability when tackling large programs. Scheme metaprogramming also serves as a gentle introduction to domain specific languages.
Pro Multiparadigm
Unlike most languages, Scheme actually accords both functional programming and imperative programming roughly equal status. Many other languages like Python and Java are staunchly imperative while SML and Haskell are primarily functional; Scheme is a nice middle ground.
Additionally, since Scheme syntax is extremely flexible, it can easily be re-purposed for teaching non-deterministic and logic programming. There is no need to learn a new language like Prolog when the same ideas can easily be expressed with Scheme syntax.
This gives students a good perspective on different ways to think about and organize programs, which makes it much easier to move forward to other languages and technologies.
Pro Catch errors at compile-time
Since Rust is statically typed, you can catch multiple errors during compile time. This is extremely helpful with debugging, especially compared with dynamically typed languages that may fail silently during runtime.
Pro Compiles to machine code allowing for extra efficiency
Rust uses LLVM as a backend, among other things this allows Rust code to compile down to machine languages. This allows developers to write programs that run as efficiently as possible.
Pro Threads without data races
Unique ownership system guarantees a mutable data to be owned and mutated by only one thread at a time, so there's no data race, and this guarantee is checked at compile time statically. Which means easy multi-threading.
Of course, immutable data can be shared among multiple threads freely.
Pro Generics support
You don't have to write same array and dictionary classes hundreds and thousands times for strong type check by compiler.
Pro Built-in concurrency
Rust has built-in support for concurrency.
Pro Supports cross compilation for different architectures
Since Rust 1.8 you can install additional versions of the standard library for different targets using rustup/multirust
.
For example:
$ rustup target add x86_64-unknown-linux-musl
Which then allows for:
$ cargo build --target x86_64-unknown-linux-musl
Pro Makes developers write optimal code
Rust is a modern programming language written around systems. It was designed from the ground up this way. It's language design makes developers write optimal code almost all the time, meaning you don't have to fully know and understand the compiler's source code in order to optimize your program.
Furthermore, Rust does not copy from memory unnecessarily, to give an example: all types move by default and not copy. Even references to types do not copy by default. In other words, setting a reference to another reference destroys the original one unless it's stated otherwise.
Pro Support for macros
When you identify a part of your code which gets repeated often, which you cannot abstract using functions or classes, you can use Rust's built-in Macros.
Pro Official package manager and build tool
Cargo is the official package manager for Rust. It comes with the language and downloads dependencies, compiles packages, and makes and uploads distributable packages
Pro Easy to write understandable code
While not as verbose as Java, it still is much more verbose than languages like Go and Python. This means that the code is very explicit and easy to understand.
Pro Big community
The biggest community contributing to language.
Pro Functional programming
Very easy to create functional with some additional from structure application.
Pro Excellent syntax
Pro Safety
Pro No GC
Pro Low memory usage
Pro Static compiled & statically linked single file output
Pro Extremely fast code execution
Pro Zero-cost futures or Async IO
Cons
Con Little job market
There are little to none jobs searching for a Scheme programmer. The ones that exist are more related to Research in Maths or Artificial Intelligence.
Con A language that is purely academic
If someone said "I am starting a project in Scheme" then they are either talking about their homework or they are starting a joke.
Con Fragmented ecosystem
Scheme is an IEEE standard, not an implementation. Unfortunately, the standard is too minimal and practical implementations have diverged--they had to expand on the standard to get anything done, but did so in incompatible ways.
The later de facto standard R6RS tried to correct this, but lost Scheme's minimalist elegance in the process. The newer R7RS standard takes the best of both worlds with an elegant minimalist core and a practical standard library.
Con Very different semantics from mainstream programming languages
LISP-like languages are very different from mainstream languages (such as C/C++/Java/JavaScript/Python/you-name-it) - both in semantics and syntax. This, in turn, severely limits uses of whatever-learned-with-Scheme, for real-world use.
Con Long compile times
Way longer to compile than other languages.
Con Low productivity
The compiler is strict, such as ownership and borrowing checkers.
Con Low readability
Harder to read and understand language.
Con Very ugly and verbose syntax
Compared to many languages. One tool needed to be productive is the language to be pleasing and effective, yet Rust friction is as high as its safety.
Con Steep learning curve
Pretty strict and hard to adapt for beginners.
Con Not as useful or productive as advertised.
If really out here wanting to use something besides C/C++, in 98% of use cases, would do just as well or be better off using something other than Rust. Will complete the project faster, would be easier, will be happier, and nearly as safe (use newer language with optional GC).
Con Rust not as safe as it pretends to be
Rust problems:
1) Massive undisclosed usage of unsafe.
2) Massive amounts of memory safety CVEs - see details.
3) Large bloated Rust binaries increase attack surface for exploits.
4) Many corporate types claiming Rust is safe, don't actually program or use it (have some quiet financial interest to push it).
Con Significant time required to understand the language fully
There's the infamous borrow checker for example.
Con Low-level programming language
This means that it encourages the programmer to be very careful in terms of how memory is allocated, etc.
Most applications can run without exceeding the capacity of the server, even with an inefficient dynamic scripting language.