Class ItemAbstract

Abstract Readonly key

Abstract Readonly length

Abstract Readonly tag

Abstract Readonly target

Abstract Readonly typeOrder

[iterator]

• [iterator](): Cursor<Item>

• Returns Cursor<Item>

Abstract alias

• alias(): void

• Returns void

Abstract and

• and(that): Item

• Parameters

  • that: Item

  Returns Item

appended

• appended(...items): Record

• Parameters

  • Rest ...items: ItemLike[]

  Returns Record

Abstract bitwiseAnd

• bitwiseAnd(that): Item

• Parameters

  • that: ItemLike

  Returns Item

Abstract bitwiseNot

• bitwiseNot(): Item

• Returns Item

Abstract bitwiseOr

• bitwiseOr(that): Item

• Parameters

  • that: ItemLike

  Returns Item

Abstract bitwiseXor

• bitwiseXor(that): Item

• Parameters

  • that: ItemLike

  Returns Item

Abstract body

• body(): Value

• Returns the [[Record.flattened flattened]] [[Item.tail tail]] of this Item. Used to recursively deconstruct a structure, terminating with its last Value, rather than a unary Record containing its last value, if the structure ends with a Value member.

  Returns Value

Abstract booleanValue

• booleanValue(): boolean

• Converts this Item into a boolean value, if possible; otherwise returns undefined if this Item can't be converted into a boolean value.

  Returns boolean
• booleanValue<T>(orElse): boolean | T

• Converts this Item into a boolean value, if possible; otherwise returns orElse if this Item can't be converted into a boolean value.

  Type Parameters

  • T

  Parameters

  • orElse: T

  Returns boolean | T

Abstract branch

• branch(): Item

• Returns Item

cast

• cast<T>(form): T

• Type Parameters

  • T

  Parameters

  • form: Form<T, unknown>

  Returns T

• cast<T, E>(form, orElse): T | E

• Type Parameters

  • T

  • E = T

  Parameters

  • form: Form<T, unknown>

  • orElse: E

  Returns T | E

Abstract clone

• clone(): Item

• Returns Item

coerce

• coerce<T>(form): T

• Type Parameters

  • T

  Parameters

  • form: Form<T, unknown>

  Returns T

• coerce<T, E>(form, orElse): T | E

• Type Parameters

  • T

  • E = T

  Parameters

  • form: Form<T, unknown>

  • orElse: E

  Returns T | E

Abstract commit

• commit(): Item

• Returns Item

Abstract compareTo

• compareTo(that): number

• Parameters

  • that: unknown

  Returns number

concat

• concat(...items): Record

• Parameters

  • Rest ...items: ItemLike[]

  Returns Record

Abstract conditional

• conditional(thenTerm, elseTerm): Item

• Parameters

  • thenTerm: Item

  • elseTerm: Item

  Returns Item

Abstract debug

• debug<T>(output): Output<T>

• Type Parameters

  • T

  Parameters

  • output: Output<T>

  Returns Output<T>

Abstract deleted

• deleted(key): Item

• Parameters

  • key: ValueLike

  Returns Item

display

• display<T>(output): Output<T>

• Type Parameters

  • T

  Parameters

  • output: Output<T>

  Returns Output<T>

Abstract divide

• divide(that): Item

• Parameters

  • that: ItemLike

  Returns Item

eq

• eq(that): Item

• Parameters

  • that: ItemLike

  Returns Item

Abstract equals

• equals(that): boolean

• Parameters

  • that: unknown

  Returns boolean

Abstract equivalentTo

• equivalentTo(that, epsilon?): boolean

• Parameters

  • that: unknown

  • Optional epsilon: number

  Returns boolean

evaluate

• evaluate(interpreter): Item

• Parameters

  • interpreter: InterpreterLike

  Returns Item

filter

• filter(predicate?): Selector

• Parameters

  • Optional predicate: ItemLike

  Returns Selector

Abstract flattened

• flattened(): Value

• Returns the sole member of this Item, if this Item is a [[Record]] with exactly one member, and its member is a Value; returns [[Extant]] if this Item is an empty Record; returns [[Absent]] if this Item is a Field; otherwise returns this if this Item is a Record with more than one member, or if this Item is a non-Record Value.

  Used to convert a unary Record into its member Value. Facilitates writing code that treats a unary Record equivalently to a bare Value.

  Returns Value

forEach

• forEach<T>(callback): T

• Type Parameters

  • T

  Parameters

  • callback: ((item, index) => void | T)

    • • (item, index): void | T

      • Parameters

        • item: Item

        • index: number

        Returns void | T

  Returns T

• forEach<T, S>(callback, thisArg): T

• Type Parameters

  • T

  • S

  Parameters

  • callback: ((this, item, index) => void | T)

    • • (this, item, index): void | T

      • Parameters

        • this: S

        • item: Item

        • index: number

        Returns void | T

  • thisArg: S

  Returns T

ge

• ge(that): Item

• Parameters

  • that: ItemLike

  Returns Item

Abstract get

• get(key): Value

• Returns the value of the last [[Field]] member of this Item whose key is equal to the given key; returns [[Absent]] if this Item is not a [[Record]], or if this Item is a Record, but has no Field member with a key equal to the given key.

  Parameters

  • key: ValueLike

  Returns Value

Abstract getAttr

• getAttr(key): Value

• Returns the value of the last [[Attr]] member of this Item whose key is equal to the given key; returns [[Absent]] if this Item is not a [[Record]], or if this Item is a Record, but has no Attr member with a key equal to the given key.

  Parameters

  • key: TextLike

  Returns Value

Abstract getField

• getField(key): Field

• Returns the last [[Field]] member of this Item whose key is equal to the given key; returns undefined if this Item is not a [[Record]], or if this Item is a Record, but has no Field member with a key equal to the given key.

  Parameters

  • key: ValueLike

  Returns Field

Abstract getItem

• getItem(index): Item

• Returns the member of this Item at the given index, if this Item is a [[Record]], and the index is greater than or equal to zero, and less than the [[Record.length length]] of the Record; otherwise returns [[Absent]] if this Item is not a Record, or if this Item is a Record, but the index is out of bounds.

  Parameters

  • index: NumLike

  Returns Item

Abstract getSlot

• getSlot(key): Value

• Returns the value of the last [[Slot]] member of this Item whose key is equal to the given key; returns [[Absent]] if this Item is not a [[Record]], or if this Item is a Record, but has no Slot member with a key equal to the given key.

  Parameters

  • key: ValueLike

  Returns Value

gt

• gt(that): Item

• Parameters

  • that: ItemLike

  Returns Item

Abstract has

• has(key): boolean

• Returns true if this Item is a [[Record]] that has a [[Field]] member with a key that is equal to the given key; otherwise returns false if this Item is not a Record, or if this Item is a Record, but has no Field member with a key equal to the given key.

  Parameters

  • key: ValueLike

  Returns boolean

Abstract hashCode

• hashCode(): number

• Returns number

Abstract head

• head(): Item

• Returns the first member of this Item, if this Item is a non-empty [[Record]]; otherwise returns [[Absent]].

  Returns Item

Abstract header

• header(tag): Value

• Returns the value of the first member of this Item, if this Item is a [[Record]], and its first member is an [[Attr]] whose key string is equal to tag; otherwise returns [[Absent]] if this Item is not a Record, or if this Item is a Record whose first member is not an Attr, or if this Item is a Record whose first member is an Attr whose key does not equal the tag.

  Used to conditionally get the value of the head Attr of a structure, if and only if the key string of the head Attr is equal to the tag. Can be used to check if a structure might conform to a nominal type named tag, while simultaneously getting the value of the tag attribute.

  Parameters

  • tag: string

  Returns Value

Abstract headers

• headers(tag): Record

• Returns the [[Item.unflattened unflattened]] [[Item.header header]] of this Item, if this Item is a [[Record]], and its first member is an [[Attr]] whose key string is equal to tag; otherwise returns undefined.

  The headers of the tag attribute of a structure are like the attributes of an XML element tag; through unlike an XML element, tag attribute headers are not limited to string keys and values.

  Parameters

  • tag: string

  Returns Record

interpolateTo

• interpolateTo(that): Interpolator<Item>

• Parameters

  • that: Item

  Returns Interpolator<Item>

• interpolateTo(that): Interpolator<Item>

• Parameters

  • that: unknown

  Returns Interpolator<Item>

Abstract inverse

• inverse(): Item

• Returns Item

invoke

• invoke(args): Item

• Parameters

  • args: Value

  Returns Item

Abstract isAliased

• isAliased(): boolean

• Returns boolean

Abstract isConstant

• isConstant(): boolean

• Returns true if this Item always [[Item.evaluate evaluates]] to the same Item.

  Returns boolean

Abstract isDefined

• isDefined(): boolean

• Returns true if this Item is not [[Absent]].

  Returns boolean

Abstract isDefinite

• isDefinite(): boolean

• Returns true if this Item is not one of: an empty Record, False, Extant, or Absent.

  Returns boolean

Abstract isDistinct

• isDistinct(): boolean

• Returns true if this Item is neither [[Extant]] nor [[Absent]].

  Returns boolean

Abstract isMutable

• isMutable(): boolean

• Returns boolean

iterator

• iterator(): Cursor<Item>

• Returns Cursor<Item>

Abstract keyEquals

• keyEquals(key): boolean

• Parameters

  • key: unknown

  Returns boolean

Abstract lambda

• lambda(template): Value

• Parameters

  • template: Value

  Returns Value

le

• le(that): Item

• Parameters

  • that: ItemLike

  Returns Item

Optional likeType

• likeType(like): void

• Parameters

  • like: string | number | boolean | Uint8Array | readonly ItemLike[] | {
        $key: ValueLike;
        $value: ValueLike;
    } | {
        [key: string]: ValueLike;
    }

  Returns void

lt

• lt(that): Item

• Parameters

  • that: ItemLike

  Returns Item

max

• max(that): Item

• Parameters

  • that: Item

  Returns Item

min

• min(that): Item

• Parameters

  • that: Item

  Returns Item

Abstract minus

• minus(that): Item

• Parameters

  • that: ItemLike

  Returns Item

Abstract modulo

• modulo(that): Item

• Parameters

  • that: ItemLike

  Returns Item

ne

• ne(that): Item

• Parameters

  • that: ItemLike

  Returns Item

Abstract negative

• negative(): Item

• Returns Item

Abstract not

• not(): Item

• Returns Item

Abstract numberValue

• numberValue(): number

• Converts this Item into a number value, if possible; otherwise returns undefined if this Item can't be converted into a number value.

  Returns number
• numberValue<T>(orElse): number | T

• Converts this Item into a number value, if possible; otherwise returns orElse if this Item can't be converted into a number value.

  Type Parameters

  • T

  Parameters

  • orElse: T

  Returns number | T

Abstract or

• or(that): Item

• Parameters

  • that: Item

  Returns Item

Abstract plus

• plus(that): Item

• Parameters

  • that: ItemLike

  Returns Item

Abstract positive

• positive(): Item

• Returns Item

prepended

• prepended(...items): Record

• Parameters

  • Rest ...items: ItemLike[]

  Returns Record

Abstract stringValue

• stringValue(): string

• Converts this Item into a string value, if possible; otherwise returns undefined if this Item can't be converted into a string value.

  Returns string
• stringValue<T>(orElse): string | T

• Converts this Item into a string value, if possible; otherwise returns orElse if this Item can't be converted into a string value.

  Type Parameters

  • T

  Parameters

  • orElse: T

  Returns string | T

substitute

• substitute(interpreter): Item

• Parameters

  • interpreter: InterpreterLike

  Returns Item

Abstract tail

• tail(): Record

• Returns a view of all but the first member of this Item, if this Item is a non-empty [[Record]]; otherwise returns an empty Record if this Item is not a Record, or if this Item is itself an empty Record.

  Returns Record

Abstract times

• times(that): Item

• Parameters

  • that: ItemLike

  Returns Item

Abstract toLike

• toLike(): ItemLike

• Returns ItemLike

toString

• toString(): string

• Returns string

Abstract toValue

• toValue(): Value

• Returns the value component of this Item, if this Item is a [[Field]]; otherwise returns this if this Item is a Value.

  Returns Value

Abstract unflattened

• unflattened(): Record

• Returns this if this Item is a [[Record]]; returns a Record containing just this Item, if this Item is [[Item.isDistinct distinct]]; otherwise returns an empty Record if this Item is [[Extant]] or [[Absent]]. Facilitates writing code that treats a bare Value equivalently to a unary Record.

  Returns Record

updated

• updated(key, value): Record

• Parameters

  • key: ValueLike

  • value: ValueLike

  Returns Record

updatedAttr

• updatedAttr(key, value): Record

• Parameters

  • key: TextLike

  • value: ValueLike

  Returns Record

updatedSlot

• updatedSlot(key, value): Record

• Parameters

  • key: ValueLike

  • value: ValueLike

  Returns Record

Static absent

• absent(): Item

• Returns Item

Static empty

• empty(): Item

• Returns Item

Static extant

• extant(): Item

• Returns Item

Static fromLike

• fromLike(item): Item

• Parameters

  • item: ItemLike

  Returns Item

Static globalScope

• globalScope(): Item

• Returns Item