The Mellow Programming Language

Mellow is an imperative language that draws influence from D, Go, and functional languages, among others. This implementation exclusively targets x86-64 Linux.

Building

The build process assumes that recent versions of the D Language compiler dmd, gcc, g++, git, and the Netwide Assembler nasm are installed.

To build the compiler, run make in the toplevel project directory. With the proper dependencies installed, and an internet connection, a simple make should build the full compiler. Note that the make process will attempt to git clone a secondary repository (the parser generator project at https://github.com/Mellow-Programming-Language/ParserGenerator), which is necessary to build the compiler.

To enable the green threads runtime, make compiler_multithread to build a version of the compiler with those features enabled.

Help

./compiler --help will provide a summary of options.

Examples

The programs under examples/ demonstrate the syntax and semantics of the Mellow language.

List of working features:

• green threads (spawn, yield)
• channels (both read and write, with implicit yield)
• full M:N multithreading scheduler
• garbage collection
• modules
• templates (for functions and struct definitions)
• recursively-definable, template-able variants/sum-types (ADTs)
• match statements
• is variant-decomposition expressions
• functions (taking arguments, returning results including multi-return)
• function pointers
• variables
• basic data types: strings, bools, integers
• arrays: array literals, slice ranges, append semantics, .length property
• control-flow statements (if-else if-else, while, foreach, etc)
• extern func FFI semantics
• expressions: comparison operators, logical operators (&&, ||, !), etc.
• then, else, coda "end block" control-flow blocks

List of unimplemented or broken (but planned) features:

• closures
• most op-equals operators
• in blocks
• out blocks
• const semantics
• sets
• hashes
• float arithmetic and comparison operators
• lambdas