@spec any([boolean() | nil]) :: boolean() | nil

The three-valued OR of the values of some tests: a true decides, and anything that is not a false leaves it open. It is what in gives for its tests (D-61), where satisfied/2 turns the open case into false.

iex> Feel.Runtime.UnaryTests.any([false, true, nil])
true
iex> Feel.Runtime.UnaryTests.any([false, nil])
nil
iex> Feel.Runtime.UnaryTests.any([false, false])
false
iex> Feel.Runtime.UnaryTests.any([])
false

@spec matches(Feel.Value.t(), Feel.Value.t(), boolean()) :: Feel.Runtime.Env.outcome()

Returns whether the input matches the value of a test that is an expression.

uses_input? says whether the expression refers to ?.

• An expression that uses ? and is a boolean (or null) is the answer itself.
• A list matches when the input equals one of its elements.
• A range matches when the input lies within it.
• Any other value matches when the input equals it: a null too, if the expression does not use ?.

The value decides and the type of the expression never does (D-209): an expression of ? that is null is null, which is not satisfied, as null < 5 is, and a null that does not come from ? (a name that is null) is equal to a null input. The analysis lowers a test to ? = expression only where that is the same.

Examples

iex> Feel.Runtime.UnaryTests.matches(Decimal.new(2), true, true)
{:ok, true}
iex> Feel.Runtime.UnaryTests.matches(Decimal.new(2), [Decimal.new(1), Decimal.new(2)], false)
{:ok, true}
iex> range = %Feel.Value.Range{start: Decimal.new(1), end: Decimal.new(5), start_included: true, end_included: false}
iex> Feel.Runtime.UnaryTests.matches(Decimal.new(5), range, false)
{:ok, false}
iex> Feel.Runtime.UnaryTests.matches(nil, nil, false)
{:ok, true}
iex> Feel.Runtime.UnaryTests.matches(nil, nil, true)
{:ok, nil}
iex> Feel.Runtime.UnaryTests.matches(Decimal.new(2), "a", false) |> elem(0)
:error

@spec member(Feel.Value.t(), Feel.Value.t(), boolean()) :: Feel.Runtime.Env.outcome()

Returns whether the value of the subject of in is a member of the value of one of its tests (D-61).

It is matches/3, except for a list, which Table 56 reads as list contains: the subject is in it when it equals an element, or lies within an element that is a range, and an element that it cannot be compared with is not equal to it, where matches/3 makes that an error.

iex> list = [Decimal.new(1), "a", Decimal.new(3)]
iex> Feel.Runtime.UnaryTests.member(Decimal.new(3), list, false)
{:ok, true}
iex> Feel.Runtime.UnaryTests.member(Decimal.new(2), list, false)
{:ok, false}
iex> range = %Feel.Value.Range{start: Decimal.new(5), end: Decimal.new(9), start_included: true, end_included: true}
iex> Feel.Runtime.UnaryTests.member(Decimal.new(6), [Decimal.new(1), range], false)
{:ok, true}
iex> Feel.Runtime.UnaryTests.member(true, [false, Decimal.new(2)], false)
{:ok, false}

A subject that is found at the front stops the search:

iex> list = [Decimal.new(1), "a", Decimal.new(3)]
iex> Feel.Runtime.UnaryTests.member(Decimal.new(1), list, false)
{:ok, true}

@spec satisfied(:any | :positive | :negated, [boolean() | nil]) :: boolean()

Returns whether unary tests are satisfied, given the value of each test.

kind is :any for -, :positive for a list of tests, and :negated for not(...). Each value is true, false or null.

iex> Feel.Runtime.UnaryTests.satisfied(:positive, [false, true])
true
iex> Feel.Runtime.UnaryTests.satisfied(:positive, [false, nil])
false
iex> Feel.Runtime.UnaryTests.satisfied(:negated, [false, false])
true
iex> Feel.Runtime.UnaryTests.satisfied(:negated, [false, nil])
false
iex> Feel.Runtime.UnaryTests.satisfied(:any, [])
true