tomo/README.md

# Tomo - Tomorrow's Language

Tomo is a statically typed, safe, simple, lightweight, efficient programming
language that cross-compiles to C. Tomo is designed to anticipate and influence
the language design decisions of the future.

```
func greeting(name:Text)->Text:
	greeting := "hello {name}!"
	words := greeting:split(" ")
	return " ":join([w:capitalize() for w in words])

func main(name="World"):
	to_say := greeting(name)
	say(to_say)
```

```bash
$ tomo hello.tm
Hello World!
$ tomo hello.tm --name=åke
Hello Åke!
$ tomo -e hello.tm
$ ./hello --name="john doe"
Hello John Doe!
```

## Features

### Performance
- Extremely high performance code generation with minimal overhead compared to C
- Extremely fast parallel compilation times
- Language-level support for out-of-the-box function caching emphasizing
	correctness
- Structs with known-at-compile-time methods, not OOP objects with vtable
	lookups

## Safety
- Memory safety (garbage collection, compiler-enforced null safety, automatic
	array bounds checking, and no uninitialized variables)
- Arithmetic overflow checking
- Type-safe strings representing different languages with automatic prevention
	of code injection
- Pattern matching with exhaustiveness checking for tagged unions

## Simplicity
- Simple, low-boilerplate type system with type inference
- Well-defined reference and value semantics and mutability rules

## User-friendliness
- Useful and efficient built-in types: arrays, hash tables, structs, tagged
	unions (sum types), cords (efficient string representation)
- Beautiful and helpful compiler and runtime error messages with emphasis on
	user-friendliness
- Full UTF8 support for all text operations
- Built-in doctests with syntax highlighting
- Automatic command line argument parsing with type safety and no need for
	libraries.
- Easy interoperability with C

## Dependencies

Tomo has a very small set of dependencies:

- The [Boehm garbage collector](https://www.hboehm.info/gc/) for runtime
	garbage collection.
- [libunistring](https://www.gnu.org/software/libunistring/) for unicode
	string support.
- a C compiler
- and libc/libm, which should definitely already be installed.

The Boehm GC and libunistring should be available on your package manager of
choice (for example, `pacman -S gc libunistring`).

## Building

The Tomo compiler can be compiled with either GCC or Clang by running `make`.

## Usage

Run a Tomo file directly:

```bash
tomo foo.tm
# Runs the program
```

Compile a Tomo file into an object file:

```bash
tomo -c foo.tm
# Output: foo.tm.o
```

Transpile a Tomo file into a C header and source file:
```bash
tomo -t foo.tm
# Outputs: foo.tm.h foo.tm.c
```

Tomo uses the environment variables (`$CC`, `$VERBOSE`, and `$AUTOFMT`), which
control the compilation/running behavior of Tomo. The default behavior is to
use `tcc` (Tiny C Compiler) for fast compilation, `VERBOSE=0`, and
`AUTOFMT='indent -kr -l100 -nbbo -nut -sob'` for autoformatting generated code.
Any of these variables may be overridden, e.g. `CC=gcc VERBOSE=1 AUTOFMT= tomo
foo.tm` (compile with GCC and verbose compiler output without autoformatting
the code).

## Installing

```
make && sudo make install
```