Enum RTk 

pub enum RTk {
    Prim(String),
    Lit(Value),
    Range {
        lo: Value,
        hi: Value,
        excl: bool,
        base: String,
    },
    Pattern {
        src: String,
        re: Regex,
    },
    Arr {
        elem: RT,
        lo: Option<i64>,
        hi: Option<i64>,
    },
    Map {
        key: RT,
        val: RT,
    },
    Union(Vec<RT>),
    IsectN(Vec<RT>),
    Rec(RecType),
    Pred {
        base: RT,
        preds: Vec<Rc<Expr>>,
    },
    Ref(RT),
    Quantity(String),
    Func {
        params: Vec<RT>,
        ret: RT,
    },
    Any,
}

the kinds of resolved types (§3)

Variants

Prim(String)

a primitive

Lit(Value)

a literal

Range

a numeric range

Fields

lo: Value

the lower bound

hi: Value

the upper bound

excl: bool

whether the upper bound is excluded

base: String

int or float

Pattern

a string pattern

Fields

src: String

its text

re: Regex

compiled

Arr

an array

Fields

elem: RT

the element type

lo: Option<i64>

the lower size bound

hi: Option<i64>

the upper size bound

Map

a map

Fields

key: RT

the key type

val: RT

the value type

Union(Vec<RT>)

a union

IsectN(Vec<RT>)

an intersection not yet merged

Rec(RecType)

a record

Pred

a predicate refinement

Fields

base: RT

the base type

preds: Vec<Rc<Expr>>

the predicates

Ref(RT)

a reference type

Quantity(String)

a quantity of a dimension

Func

a function type

Fields

params: Vec<RT>

the parameter types

ret: RT

the return type

Any

any value