Coerce v1.0.1 Coerce View Source

Coerce allows defining coercions between data types.

These are standardized conversions of one kind of data to another. A coercion can be defined using defcoercion.

The code that coercion is compiled to attempts to ensure that the result is relatively fast (with the possibility for further optimization in the future).

Coerce does not come with built-in coercions, instead allowing libraries that build on top of it to define their own rules.

Link to this section Summary

Functions

coerce(a, b)

Performs value coercion,

defcoercion(first_module, second_module, list)

Define a coercion between two data types

Link to this section Functions

coerce(a, b)

coerce(a, b) :: {a, a} | {b, b} when a: any, b: any

Performs value coercion,

the simpler of the two values is converted into a more complex type, and the result is returned as tuple.

Examples

iex> require Coerce
iex> Coerce.defcoercion(Integer, Float) do
iex>   def coerce(int, float) do
iex>     {int + 0.0, float}
iex>   end
iex> end
iex> Coerce.coerce(1, 2.3)
{1.0, 2.3}
iex> Coerce.coerce(1.4, 42)
{1.4, 42.0}


iex> require Coerce
iex> Coerce.defcoercion(BitString, Atom) do
iex>   def coerce(str, atom) do
iex>     {str, inspect(atom)}
iex>   end
iex> end
iex> Coerce.coerce("foo", Bar)
{"foo", "Bar"}
iex> Coerce.coerce("baz", :qux)
{"baz", ":qux"}

defcoercion(first_module, second_module, list) (macro)

Define a coercion between two data types.

Expects two module names as the first two arguments and a do-block as third argument. A Coerc.CompileError will be raised at compile-time if the coercion macro is called improperly.