Wednesday, October 12, 2011

Clojure will not work

Clojure will not work. Here is why it will not work.

Based on:

Programming Language Checklist

by Colin McMillen, Jason Reed, and Elly Jones.

Slightly modified for clearer rant

You appear to be advocating a new:
[x] functional  [ ] imperative  [x] object-oriented  [ ] procedural [ ] stack-based
[ ] "multi-paradigm"  [x] lazy  [ ] eager  [ ] statically-typed  [x] dynamically-typed
[x] pure  [ ] impure  [ ] non-hygienic  [ ] visual  [ ] beginner-friendly
[ ] non-programmer-friendly  [x] completely incomprehensible
programming language.  Your language will not work.  Here is why it will not work.

You appear to believe that:
[ ] Syntax is what makes programming difficult
[x] Garbage collection is free                [ ] Computers have infinite memory
[ ] Nobody really needs:
    [ ] concurrency  [ ] a REPL  [x] debugger support  [ ] IDE support  [ ] I/O
    [ ] to interact with code not written in your language
[ ] The entire world speaks 7-bit ASCII
[x] Scaling up to large software projects will be easy
[x] Convincing programmers to adopt a new language will be easy
[x] Convincing programmers to adopt a language-specific IDE will be easy
[ ] Programmers love writing lots of boilerplate
[ ] Specifying behaviors as "undefined" means that programmers won't rely on them
[ ] "Spooky action at a distance" makes programming more fun

Unfortunately, your language has (checked only *unfortunate features*, Clojure has tail recursion):
[ ] semicolons  [ ] significant whitespace  [x] macros
[x] implicit type conversion  [ ] explicit casting  [ ] type inference
[ ] goto  [x] exceptions  [ ] coroutines
[x] reflection  [ ] subtyping  [ ] operator overloading
[ ] algebraic datatypes  [ ] recursive types  [ ] polymorphic types
[ ] covariant array typing  [ ] dependent types
[x] infix operators  
[ ] call-by-value  [ ] call-by-name  [ ] call-by-reference  [ ] call-cc

Unfortunately, your language lacks:
[ ] comprehensible syntax  [ ] macros
[ ] implicit type conversion   [ ] type inference
[ ] goto  [ ] exceptions  [ ] closures  [ ] tail recursion  [ ] coroutines
[ ] reflection  [ ] subtyping  [x] multiple inheritance  [ ] operator overloading
[ ] algebraic datatypes  [ ] recursive types  [ ] polymorphic types
[ ] covariant array typing  [ ] monads  [ ] dependent types
[ ] infix operators  [x] nested comments  [x] multi-line strings  [ ] regexes
[ ] call-by-value  [ ] call-by-name  [ ] call-by-reference  [ ] call-cc

The following philosophical objections apply:
[ ] Programmers should not need to understand category theory to write "Hello, World!"
[ ] Programmers should not develop RSI from writing "Hello, World!"
[ ] The most significant program written in your language is its own compiler
[x] The most significant program written in your language isn't even its own compiler
[ ] No language spec
[x] "The implementation is the spec"
   [ ] The implementation is closed-source  [ ] covered by patents  [ ] not owned by you
[ ] Your type system is unsound  [ ] Your language cannot be unambiguously parsed
   [ ] a proof of same is attached
   [ ] invoking this proof crashes the compiler
[ ] The name of your language makes it impossible to find on Google
[x] Interpreted languages will never be as fast as C
[ ] Compiled languages will never be "extensible"
[ ] Writing a compiler that understands English is AI-complete
[ ] Your language relies on an optimization which has never been shown possible
[x] There are less than 100 programmers on Earth smart enough to use your language
[ ] ____________________________ takes exponential time
[ ] ____________________________ is known to be undecidable

Your implementation has the following flaws:
[x] CPUs do not work that way
[ ] RAM does not work that way
[ ] VMs do not work that way
[ ] Compilers do not work that way
[x] Compilers cannot work that way
[ ] Shift-reduce conflicts in parsing seem to be resolved using rand()
[x] You require the compiler to be present at runtime
[x] You require the language runtime to be present at compile-time
[x] Your compiler errors are completely inscrutable
[ ] Dangerous behavior is only a warning
[ ] The compiler crashes if you look at it funny
[x] The VM crashes if you look at it funny  (see example below) 
[ ] You don't seem to understand basic optimization techniques
[ ] You don't seem to understand basic systems programming
[ ] You don't seem to understand pointers
[ ] You don't seem to understand functions

Additionally, your marketing has the following problems:
[x] Unsupported claims of increased productivity
[ ] Unsupported claims of greater "ease of use"
[ ] Obviously rigged benchmarks
   [ ] Graphics, simulation, or crypto benchmarks where your code just calls
       handwritten assembly through your FFI
   [ ] String-processing benchmarks where you just call PCRE
   [ ] Matrix-math benchmarks where you just call BLAS
[x] Noone really believes that your language is faster than:
    [x] assembly  [x] C  [x] FORTRAN  [x] Java  [x] Ruby  [ ] Prolog
[ ] Rejection of orthodox programming-language theory without justification
[ ] Rejection of orthodox systems programming without justification
[ ] Rejection of orthodox algorithmic theory without justification
[ ] Rejection of basic computer science without justification

Taking the wider ecosystem into account, I would like to note that:
[ ] Your complex sample code would be one line in: _______________________
[ ] We already have an unsafe imperative language
[ ] We already have a safe imperative OO language
[ ] We already have a safe statically-typed eager functional language
[ ] You have reinvented Lisp but worse
[ ] You have reinvented Javascript but worse
[ ] You have reinvented Java but worse
[ ] You have reinvented C++ but worse
[ ] You have reinvented PHP but worse
[ ] You have reinvented PHP better, but that's still no justification
[x] You have reinvented Brainfuck but non-ironically

In conclusion, this is what I think of you:
[x] You have some interesting ideas, but this won't fly.
[ ] This is a bad language, and you should feel bad for inventing it.
[ ] Programming in this language is an adequate punishment for inventing it.

examples

"The VM crashes if you look at it funny":
user=> (defmacro re2 [x] (str "a" ~x))
#'user/re2
user=> (re2 1)
java.lang.IllegalStateException: Var clojure.core/unquote is unbound. (NO_SOURCE_FILE:0)
(only few people on Earth understand this error and actually no one of them understands why this error is not presented by compiler while defmacro)