sschellhoff / fml

A simple dynamic language

Friendly Multi-paradigm Language

It is highly inspired by Bob Nystroms crafting interpreters and Thorsten Balls Writing an interpreter in go

You can start the program without any arguments to get a really simple repl. Or you can add a filepath as an argument to run a file of code.

Building

Set GOPATH properly to the starting directory. Then run make in the code directory (src/language).

On linux, run export GOPATH=$(pwd), then go to the code directory cd src/language and run the makefile make.
To run the interpreters REPL: ./interpreter, to run a file, run ./interpreter filepath. For example: ./interpreter examples/project_euler_001.fml.

Examples

src/language/examples

Core library

Set environment variable FMLPATH to the absolute path of src/language/corelibrary.

Coming soon

• plugins (for own code wrappers and stuff)
• more tests
• lots of refactoring

fml's Issues

Add core module path via environment variable

There should be a module path for the core module. It should be given via an environment variable.

Add escape sequences for strings

There should be espace sequences for strings like in other languages
\n -> linebreak
\t -> tab
\\ -> \
and so on

Add position information to parser errors

Like the scanner, the parser should add position information (line and column) to errors.

Relative import paths behave wrong

Import paths are resolves from the starting point of the program. So by running the interpreter on some *.fml file, this file is treated as the starting point for all imports. Even for imports from other files on other paths.
Relative import paths should start from the file which containts the import.
Example:

/main.fml
/submodules/module1.fml
/submodules/module2.fml

in main.fml, you should use submodules/module2.fml to import module 2, but in submodules/module1.fml you should just use module2.fml to import module 2.

Remove the need for semicolons

Semicolons should be optional. In most cases a semicolon is not important to express code. But in some cases, it can be useful. So optional semicolons are great.

Multiline comment problem

**/ does not end a multiline comment.

Example:
/*
some
comment
**/

results in an unexpected end of file.

Add stacktrace to runtime errors

Add index to strings

Strings should be indexable.