Hymn Programming Language

Hymn is a programming language designed to simplify writing complex software.

It focuses on simplicity and visually pleasing syntax without sacrificing critical features such as static typing.

Hymn compiles to readable C code, and can easily be included in existing projects.

class vec
    x int
    y int

enum result<a,b>
    ok(value a)
    error(message b)

def main   
    v = vec(2, 3)
    r = result<vec,string>.ok(v)
    match r
        ok(o): echo("vec =", o.value.x, o.value.y)
        error(e): echo("error =", e.message)

Links

• Homepage
• Read the book
• Learn by example

Why Hymn?

• Maybe<> type and strict match statements prevent null pointer exceptions
• Safe union types. Unions are used through enum types and always require matching
• Predictable runtime, there is no garbage collection
• Compiles to C. Fully usable with existing or future C projects
• Small binary size

1. Why not Python?
   • Interpreted languages are too slow for many use-cases.
   • Dynamic types can make large programs difficult to reason with.
2. Why not Golang?
   • Lack of generics can make some programs otherwise tedious to code.
   • Lack of tagged union types reduces expressiveness.
3. Why not Rust?
   • Often difficult to understand, with a high entry barrier to learning
   • Often too much for less critical software
4. Why not C?
   • Lack of conveniences such as generics and name-spaces
   • Often too easy to make critical mistakes
5. Why not C++?
   • Slow compile times compared to C
   • Considered bloated with many legacy problems

Visit the website to learn more!

Development

Completed

• Generics
• Goto and Labels
• Enums with Unions
• Classes
• Match statements
• Defining stack or heap variables
• Function pointers
• Slices and arrays
• Class functions with generics
• Automatic or manual default parameters using _
• $HYMN_LIBC environment variable and -d flag locates the standard hymn c library
• Package management using $HYMN_PACKAGES environment variable
• Multiline string declaration using ''
• Interfaces

Not Started

• References to primitives
• Multiple return values
• Bootstrapping compiler from golang to hymn
• Borrow checker
• Free heap space
• Threads / async await (split function in half for each await)
• Generate makefiles
• Macros / def
• Better error output
• Language server protocol: The compiler should have flags for how to format/output found problems and at what point to stop
• Optimize printf for multiple strings to avoid concatenation

Libraries

The standard libraries will need to include the following

• ref/ptr class for holding pointers to primitives
• tuple class for returning multiple values
• hashmap, hashset, list classes for standard data structures
• either enum for union returns
• string builder class

Bugs

• Variable scoping

Testing

• Need matching C code