Built-in Types

Grain provides some built-in types to be used throughout your programs.

Bool

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enum Bool {
  true,
  false
}

The type of Grain booleans, i.e. true or false.

Char

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type Char

The type of Grain Unicode characters, e.g. 'g', '🌾', '💻'.

String

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type String

The type of Grain strings, e.g. "The quick brown fox jumps over the lazy dog.".

Bytes

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type Bytes

The type of Grain byte sequences, e.g. b"The quick brown fox jumps over the lazy dog."

Void

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enum Void {
  void
}

The type of void, Grain’s special type for indicating the absence of a meaningful value i.e. Grain’s unit type.

Option

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enum Option<a> {
  Some(a),
  None
}

The type of Grain options (e.g. Some(1) or None). The a is the type of the value. Options are analagous to nullable values in some other languages, but are much safer to work with due to the nullability being encoded explicitly in the type.

Result

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enum Result<t, e> {
  Ok(t),
  Err(e)
}

The type of Grain results (e.g. Ok(1) or Err("Something went wrong")). The t and e are the types of the value and error, respectively. This is useful for functions that might fail.

Array

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type Array<a>

The type of Grain arrays, e.g. [> 1, 2, 3]. Arrays are fixed-length and allow for efficient get/set operations at any index.

List

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type List<a>

The type of Grain lists (linked lists), e.g. [1, 2, 3]. Lists are immutable and allow for values to be efficiently appended.

Box

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type Box<a>

The type of Grain boxes. Boxes are wrappers that allow the internal data to be swapped during execution.

Rational

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type Rational

The type of Grain rationals, e.g. 2/3r. Rationals are represented as a numerator and denominator.

Number

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type Number

The type of Grain numbers, e.g. 42, 0x2a, 23.19, 2/3. Grain numbers can be arbitrarily large integers, floats, or rationals.

BigInt

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type BigInt

The type of arbitrarily large integers, e.g. 42t, 9_223_372_036_854_775_808t.

Int8

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type Int8

The type of 8-bit integers, e.g. 127s, -127s, 0x01s.

Uint8

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type Uint8

The type of 8-bit unsigned integers, e.g. 255us, 42us, 0x01us.

Int16

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type Int16

The type of 16-bit integers, e.g. 32768S, -32768S, 0x01S.

Uint16

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type Uint16

The type of 16-bit unsigned integers, e.g. 65535uS, 42uS, 0x01uS.

Int32

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type Int32

The type of 32-bit integers, e.g. 42l, 0x2al.

Uint32

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type Uint32

The type of 32-bit unsigned integers, e.g. 42ul, 0x2aul.

Int64

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type Int64

The type of 64-bit integers, e.g. 42L, 0x2aL.

Uint64

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type Uint64

The type of 64-bit unsigned integers, e.g. 42uL, 0x2auL.

Float32

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type Float32

The type of 32-bit floating-point numbers, e.g. 3.5f.

Float64

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type Float64

The type of 64-bit floating-point numbers, e.g. 3.5d.

Exception

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type Exception

The type of Grain exceptions. Exceptions represent errors that have occured in a program.