tin

tin is a new statically structurally typed programming language. It's main purpose is to be embedded in other programs (similar to e.g. Lua) but built to easily be compilable (initially JIT).

tin is what you need to create the solder for your application. It's easy to build plugin APIs that are type safe using tin.

Despite tin having the chemical symbol Sn, tin files conventionally use the .tn extension because it's easier to remember the mnemonic.

Currently, the language is a work in progress. The MVP will be a Rust library and executable called tin that include a JIT compiler and rudimentary type inference.

Example

tin is purely expression oriented; there are no types per se. In order to define a type, you give an example value for the type. This is very similar to prototype-based type systems, except there is no support for inheritance.

/* Defines the Int type by giving an example value */
Int = 0i64;
/* Similarly for String */
String = "";

/* A Person is anything that has both a name of type String and an age of type Int
 * The definintion is identical to: { name: "", age: 0i64 }
 */
Person = { name: String, age: Int };

Everything is either an expression or a variable definition. There are for example no functions; there are only lambdas which can be assigned to variables:

getAge = |person: Person| Int { person.age };

tin supports structural polymorphic type inference:

getAge = |person| { person.age };

main = || {
  getAge({age: 3}); /* → returns 3 */
  getAge({age: "Hello"}); /* → returns "Hello" */
  getAge({name: "Hello"}) /* compile time error */
};

tin has several built-in types:

/* An unsigned 8-bit integer */
ExampleU8 = 0u8;
/* An unsigned 16-bit integer */
ExampleU16 = 0u16;
/* An unsigned 32-bit integer */
ExampleU32 = 0u32;
/* An unsigned 64-bit integer */
ExampleU64 = 0u64;

/* A signed 8-bit integer */
ExampleI8 = 0i8;
/* A signed 16-bit integer */
ExampleI16 = 0i16;
/* A signed 32-bit integer */
ExampleI32 = 0i32;
/* A signed 64-bit integer */
ExampleI64 = 0i64;

/* A 32 bit floating point number */
ExampleF32 = 0.0f32;
/* A 64 bit floating point number */
ExampleF64 = 0.0f64;

/* An UTF-8 string */
ExampleString = "";

/* A symbol value */
ExampleSymbol = :foo;

/* A tuple */
ExampleTuple = (String, I8, I8);
/* A record */
ExampleRecord = { name: String, x: I8, y: I8 };

/* A lambda */
ExampleLambda = |tuple: ExampleTuple, record: ExampleRecord, int: I8| I8 { int };