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Future

A few people have asked me about the future of this language, specifically if I will ever come back to it. I have some rather complicated feelings, as one might expect of a project spanning a decade. Additionally, I don't think that a README is a good space to air those feelings out.

Due to an event that happened in my life since pausing on Lily, I will not be providing any further updates to it. I am going to, instead, redirect my energy to other projects.

To those who helped with Lily's progress: Thank you.

Lily

Lily is a programming language focused on expressiveness and type safety.

Sample

scoped enum Color { Black, Blue, Cyan, Green, Magenta, Red, White, Yellow }

class Terminal(public var @foreground: Color, width_str: String)
{
    public var @width = width_str.parse_i().unwrap_or(80)

    public define set_fg(new_color: Color) {
        @foreground = new_color
    }
}

var terms = [Terminal(Color.White, "A"), Terminal(Color.Red, "40")]

terms.each(|e| e.width += 20 )
     |> print

Features

Templating

By default, Lily runs in standalone mode where all content is code to execute. But Lily can also be run in template mode. In template mode, code is between <?lily ... ?> tags. When a file is imported, it's always loaded in standalone mode, so that it doesn't accidentally send headers. Files that are imported are also namespaced (no 'global namespace').

Embeddable

Lily may be a statically-typed language, but the reference implementation is an interpreter. The interpreter as well as its API have been carefully designed with sandboxing in mind. As a result, it's possible to have multiple interpreters exist alongside each other.

Shorter edit cycle

Another benefit from having the reference implementation as an interpreter is a shorter turn around time. The interpreter's parser is comparable in speed to that of languages using an interpreter as their reference.

Building

You need a C compiler and CMake (3.0.0 +). There are no external dependencies.

To build Lily, execute the following in a terminal:

cmake .

make

Note: Windows users may need to add -G"Unix Makefiles" to the end of the cmake invocation.

The above will build the lily executable, as well as a liblily that you can use with your program. It also builds pre-commit-tests.

Running tests

The centerpiece of Lily's testing is test_main.lily in the test directory. That file imports and invokes a large number of tests that cover a lot of Lily.

The make command also builds covlib and pre-commit-tests. No additional commands are necessary. covlib is a library that tests some parts of Lily that native code can't test. pre-commit-tests is a special runner that executes test_main.lily.

To run Lily's tests, execute pre-commit-tests from the directory it's in after building Lily.

Resources

Packaging

The lily-garden repository contains a package manager (Garden) that simplifies the install of Lily packages.

License

MIT