All Implemented Interfaces:: Comparable<Item>, Iterable<Item>, Debug, Display

Direct Known Subclasses:: Field, Value

public abstract class Item
extends Object
implements Comparable<Item>, Iterable<Item>, Debug, Display

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method	Description
`static Item`	`absent()`
`abstract void`	`alias()`
`abstract Item`	`and(Item that)`
`Record`	`appended(boolean item)`
`Record`	`appended(double item)`
`Record`	`appended(float item)`
`Record`	`appended(int item)`
`Record`	`appended(long item)`
`Record`	`appended(Object... items)`
`Record`	`appended(String item)`
`Record`	`appended(Item item)`
`abstract Item`	`bitwiseAnd(Item that)`
`abstract Item`	`bitwiseNot()`
`abstract Item`	`bitwiseOr(Item that)`
`abstract Item`	`bitwiseXor(Item that)`
`abstract Value`	`body()`	Returns the `flattened` `tail` of this `Item`.
`abstract boolean`	`booleanValue()`	Converts this `Item` into a primitive `boolean` value, if possible.
`abstract boolean`	`booleanValue(boolean orElse)`	Converts this `Item` into a primitive `boolean` value, if possible; otherwise returns `orElse` if this `Item` can't be converted into a primitive `boolean` value.
`abstract Item`	`branch()`
`abstract byte`	`byteValue()`	Converts this `Item` into a primitive `byte` value, if possible.
`abstract byte`	`byteValue(byte orElse)`	Converts this `Item` into a primitive `byte` value, if possible; otherwise returns `orElse` if this `Item` can't be converted into a primitive `byte` value.
`<T> T`	`cast(Form<T> form)`
`<T> T`	`cast(Form<T> form, T orElse)`
`abstract char`	`charValue()`	Converts this `Item` into a primitive `char` value, if possible.
`abstract char`	`charValue(char orElse)`	Converts this `Item` into a primitive `char` value, if possible; otherwise returns `orElse` if this `Item` can't be converted into a primitive `char` value.
`<T> T`	`coerce(Form<T> form)`
`<T> T`	`coerce(Form<T> form, T orElse)`
`abstract Item`	`commit()`	Flags this `Item` as immutable, recursively if it is a `Record`, then returns this `Item`.
`abstract int`	`compareTo(Item other)`
`Record`	`concat(Item that)`
`abstract Item`	`conditional(Item thenTerm, Item elseTerm)`
`abstract boolean`	`contains(Item item)`	Returns `true` if this `Item` is a `Record` that has a member equal to `item`; otherwise returns `false` if this `Item` is not a `Record`, or if this `Item` is a `Record`, but has no member equal to `item`.
`abstract boolean`	`containsKey(String key)`	Returns `true` if this `Item` is a `Record` that has a `Field` with a `Text` key whose string value 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 `Text` key whose string value equals the given `key`.
`abstract boolean`	`containsKey(Value key)`	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`.
`abstract boolean`	`containsValue(Value value)`	Returns `true` if this `Item` is a `Record` that has a `Field` member with a value that is equal to the given `value`; otherwise returns `false` if this `Item` is not a `Record`, or if this `Item` is a `Record`, but has no `Field` member with a value equal to the given `value`.
`abstract <T> Output<T>`	`debug(Output<T> output)`	Writes a developer readable, debug-formatted string representation of this object to `output`.
`<T> Output<T>`	`display(Output<T> output)`	Writes a human readable, display-formatted string representation of this object to `output`.
`abstract Item`	`divide(Item that)`
`abstract double`	`doubleValue()`	Converts this `Item` into a primitive `double` value, if possible.
`abstract double`	`doubleValue(double orElse)`	Converts this `Item` into a primitive `double` value, if possible; otherwise returns `orElse` if this `Item` can't be converted into a primitive `double` value.
`static Item`	`empty()`
`Item`	`eq(Item that)`
`abstract boolean`	`equals(Object other)`
`Item`	`evaluate(Interpreter interpreter)`
`Item`	`evaluate(Item scope)`
`static Item`	`extant()`
`Selector`	`filter()`
`Selector`	`filter(Item predicate)`
`abstract Value`	`flattened()`	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`.
`abstract float`	`floatValue()`	Converts this `Item` into a primitive `float` value, if possible.
`abstract float`	`floatValue(float orElse)`	Converts this `Item` into a primitive `float` value, if possible; otherwise returns `orElse` if this `Item` can't be converted into a primitive `float` value.
`static Item`	`fromObject(Object object)`
`Item`	`ge(Item that)`
`abstract Value`	`get(String key)`	Returns the value of the last `Field` member of this `Item` with a `Text` key whose string value 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 `Text` key whose string value equals the given `key`.
`abstract Value`	`get(Value key)`	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`.
`abstract Value`	`getAttr(String key)`	Returns the value of the last `Attr` member of this `Item` with a `Text` key whose string value 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 `Text` key whose string value equals the given `key`.
`abstract Value`	`getAttr(Text key)`	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`.
`abstract Field`	`getField(String key)`	Returns the last `Field` member of this `Item` with a `Text` key whose string value is equal to the given `key`; returns `null` if this `Item` is not a `Record`, or if this `Item` is a `Record`, but has no `Field` member with a `Text` key whose string value equals the given `key`.
`abstract Field`	`getField(Value key)`	Returns the last `Field` member of this `Item` whose key is equal to the given `key`; returns `null` 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`.
`abstract Item`	`getItem(int index)`	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 `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.
`abstract Value`	`getSlot(String key)`	Returns the value of the last `Slot` member of this `Item` with a `Text` key whose string value 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 `Text` key whose string value equals the given `key`.
`abstract Value`	`getSlot(Value key)`	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`.
`static Item`	`globalScope()`
`Item`	`gt(Item that)`
`abstract int`	`hashCode()`
`abstract Item`	`head()`	Returns the first member of this `Item`, if this `Item` is a non-empty `Record`; otherwise returns `Absent`.
`abstract Value`	`header(String tag)`	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`.
`abstract Record`	`headers(String tag)`	Returns the `unflattened` `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 `null`.
`abstract BigInteger`	`integerValue()`	Converts this `Item` into a `BigInteger` value, if possible.
`abstract BigInteger`	`integerValue(BigInteger orElse)`	Converts this `Item` into a `BigInteger` value, if possible; otherwise returns `orElse` if this `Item` can't be converted into a `BigInteger` value.
`abstract int`	`intValue()`	Converts this `Item` into a primitive `int` value, if possible.
`abstract int`	`intValue(int orElse)`	Converts this `Item` into a primitive `int` value, if possible; otherwise returns `orElse` if this `Item` can't be converted into a primitive `int` value.
`abstract Item`	`inverse()`
`Item`	`invoke(Value args)`
`abstract boolean`	`isAliased()`
`abstract boolean`	`isConstant()`	Returns `true` if this `Item` always `evaluates` to the same `Item`.
`abstract boolean`	`isDefined()`	Returns `true` if this `Item` is not `Absent`.
`abstract boolean`	`isDefinite()`	Returns `true` if this `Item` is not one of: an empty `Record`, `False`, `Extant`, or `Absent`.
`abstract boolean`	`isDistinct()`	Returns `true` if this `Item` is neither `Extant` nor `Absent`.
`abstract boolean`	`isMutable()`
`Iterator<Item>`	`iterator()`
`abstract Value`	`key()`	Returns the key component of this `Item`, if this `Item` is a `Field`; otherwise returns `Absent` if this `Item` is a `Value`.
`abstract boolean`	`keyEquals(Object key)`
`abstract Value`	`lambda(Value template)`
`Item`	`le(Item that)`
`abstract int`	`length()`	Returns the number of members contained in this `Item`, if this `Item` is a `Record`; otherwise returns `0` if this `Item` is not a `Record`.
`abstract long`	`longValue()`	Converts this `Item` into a primitive `long` value, if possible.
`abstract long`	`longValue(long orElse)`	Converts this `Item` into a primitive `long` value, if possible; otherwise returns `orElse` if this `Item` can't be converted into a primitive `long` value.
`Item`	`lt(Item that)`
`Item`	`max(Item that)`
`Item`	`min(Item that)`
`abstract Item`	`minus(Item that)`
`abstract Item`	`modulo(Item that)`
`Item`	`ne(Item that)`
`abstract Item`	`negative()`
`abstract Item`	`not()`
`abstract Number`	`numberValue()`	Converts this `Item` into a `Number` object, if possible.
`abstract Number`	`numberValue(Number orElse)`	Converts this `Item` into a `Number` object, if possible; otherwise returns `orElse` if this `Item` can't be converted into a `Number` object.
`abstract Item`	`or(Item that)`
`abstract Item`	`plus(Item that)`
`abstract Item`	`positive()`
`int`	`precedence()`
`Record`	`prepended(boolean item)`
`Record`	`prepended(double item)`
`Record`	`prepended(float item)`
`Record`	`prepended(int item)`
`Record`	`prepended(long item)`
`Record`	`prepended(Object... items)`
`Record`	`prepended(String item)`
`Record`	`prepended(Item item)`
`abstract Item`	`removed(String key)`
`abstract Item`	`removed(Value key)`
`abstract short`	`shortValue()`	Converts this `Item` into a primitive `short` value, if possible.
`abstract short`	`shortValue(short orElse)`	Converts this `Item` into a primitive `short` value, if possible; otherwise returns `orElse` if this `Item` can't be converted into a primitive `short` value.
`abstract String`	`stringValue()`	Converts this `Item` into a `String` value, if possible.
`abstract String`	`stringValue(String orElse)`	Converts this `Item` into a `String` value, if possible; otherwise returns `orElse` if this `Item` can't be converted into a `string` value.
`Item`	`substitute(Interpreter interpreter)`
`Item`	`substitute(Item scope)`
`abstract String`	`tag()`	Returns the `key` string of the first member of this `Item`, if this `Item` is a `Record`, and its first member is an `Attr`; otherwise returns `null` if this `Item` is not a `Record`, or if this `Item` is a `Record` whose first member is not an `Attr`.
`abstract Record`	`tail()`	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`.
`abstract Value`	`target()`	Returns the `flattened` members of this `Item` after all attributes have been removed, if this `Item` is a `Record`; otherwise returns `this` if this `Item` is a non-`Record` `Value`, or returns the value component if this `Item` is a `Field`.
`abstract Item`	`times(Item that)`
`String`	`toString()`
`abstract Value`	`toValue()`	Returns the value component of this `Item`, if this `Item` is a `Field`; otherwise returns `this` if this `Item` is a `Value`.
`abstract int`	`typeOrder()`	Returns the heterogeneous sort order of this `Item`.
`abstract Record`	`unflattened()`	Returns `this` if this `Item` is a `Record`; returns a `Record` containing just this `Item`, if this `Item` is `distinct`; otherwise returns an empty `Record` if this `Item` is `Extant` or `Absent`.
`Record`	`updated(String key, boolean value)`
`Record`	`updated(String key, double value)`
`Record`	`updated(String key, float value)`
`Record`	`updated(String key, int value)`
`Record`	`updated(String key, long value)`
`Record`	`updated(String key, String value)`
`Record`	`updated(String key, Value value)`
`Record`	`updated(Value key, boolean value)`
`Record`	`updated(Value key, double value)`
`Record`	`updated(Value key, float value)`
`Record`	`updated(Value key, int value)`
`Record`	`updated(Value key, long value)`
`Record`	`updated(Value key, String value)`
`Record`	`updated(Value key, Value value)`
`Record`	`updatedAttr(String key, boolean value)`
`Record`	`updatedAttr(String key, double value)`
`Record`	`updatedAttr(String key, float value)`
`Record`	`updatedAttr(String key, int value)`
`Record`	`updatedAttr(String key, long value)`
`Record`	`updatedAttr(String key, String value)`
`Record`	`updatedAttr(String key, Value value)`
`Record`	`updatedAttr(Text key, boolean value)`
`Record`	`updatedAttr(Text key, double value)`
`Record`	`updatedAttr(Text key, float value)`
`Record`	`updatedAttr(Text key, int value)`
`Record`	`updatedAttr(Text key, long value)`
`Record`	`updatedAttr(Text key, String value)`
`Record`	`updatedAttr(Text key, Value value)`
`Record`	`updatedSlot(String key, boolean value)`
`Record`	`updatedSlot(String key, double value)`
`Record`	`updatedSlot(String key, float value)`
`Record`	`updatedSlot(String key, int value)`
`Record`	`updatedSlot(String key, long value)`
`Record`	`updatedSlot(String key, String value)`
`Record`	`updatedSlot(String key, Value value)`
`Record`	`updatedSlot(Value key, boolean value)`
`Record`	`updatedSlot(Value key, double value)`
`Record`	`updatedSlot(Value key, float value)`
`Record`	`updatedSlot(Value key, int value)`
`Record`	`updatedSlot(Value key, long value)`
`Record`	`updatedSlot(Value key, String value)`
`Record`	`updatedSlot(Value key, Value value)`

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.Iterable
forEach, spliterator

- Method Detail
  - isDefined
```
public abstract boolean isDefined()
```
    Returns true if this Item is not Absent.
  - isDistinct
```
public abstract boolean isDistinct()
```
    Returns true if this Item is neither Extant nor Absent.
  - isDefinite
```
public abstract boolean isDefinite()
```
    Returns true if this Item is not one of: an empty Record, False, Extant, or Absent.
  - isConstant
```
public abstract boolean isConstant()
```
    Returns true if this Item always evaluates to the same Item.
  - key
```
public abstract Value key()
```
    Returns the key component of this Item, if this Item is a Field; otherwise returns Absent if this Item is a Value.
  - toValue
```
public abstract Value toValue()
```
    Returns the value component of this Item, if this Item is a Field; otherwise returns this if this Item is a Value.
  - tag
```
public abstract String tag()
```
    Returns the key string of the first member of this Item, if this Item is a Record, and its first member is an Attr; otherwise returns null if this Item is not a Record, or if this Item is a Record whose first member is not an Attr.
    Used to concisely get the name of the discriminating attribute of a structure. The tag can be used to discern the nominal type of a polymorphic structure, similar to an XML element tag.
  - target
```
public abstract Value target()
```
    Returns the flattened members of this Item after all attributes have been removed, if this Item is a Record; otherwise returns this if this Item is a non-Record Value, or returns the value component if this Item is a Field.
    Used to concisely get the scalar value of an attributed structure. An attributed structure is a Record with one or more attributes that modify one or more other members.
  - flattened
```
public abstract Value flattened()
```
    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.
  - unflattened
```
public abstract Record unflattened()
```
    Returns this if this Item is a Record; returns a Record containing just this Item, if this Item is 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.
  - header
```
public abstract Value header(String tag)
```
    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.
  - headers
```
public abstract Record headers(String tag)
```
    Returns the unflattened 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 null.
    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.
  - head
```
public abstract Item head()
```
    Returns the first member of this Item, if this Item is a non-empty Record; otherwise returns Absent.
  - tail
```
public abstract Record tail()
```
    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.
  - body
```
public abstract Value body()
```
    Returns the flattened 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.
  - length
```
public abstract int length()
```
    Returns the number of members contained in this Item, if this Item is a Record; otherwise returns 0 if this Item is not a Record.
  - contains
```
public abstract boolean contains(Item item)
```
    Returns true if this Item is a Record that has a member equal to item; otherwise returns false if this Item is not a Record, or if this Item is a Record, but has no member equal to item.
  - containsKey
```
public abstract boolean containsKey(Value key)
```
    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.
  - containsKey
```
public abstract boolean containsKey(String key)
```
    Returns true if this Item is a Record that has a Field with a Text key whose string value 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 Text key whose string value equals the given key. Equivalent to containsKey(Value), but avoids boxing the key string into a Text value.
  - containsValue
```
public abstract boolean containsValue(Value value)
```
    Returns true if this Item is a Record that has a Field member with a value that is equal to the given value; otherwise returns false if this Item is not a Record, or if this Item is a Record, but has no Field member with a value equal to the given value.
  - get
```
public abstract Value get(Value key)
```
    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.
  - get
```
public abstract Value get(String key)
```
    Returns the value of the last Field member of this Item with a Text key whose string value 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 Text key whose string value equals the given key. Equivalent to get(Value), but avoids boxing the key string into a Text value.
  - getAttr
```
public abstract Value getAttr(Text key)
```
    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.
  - getAttr
```
public abstract Value getAttr(String key)
```
    Returns the value of the last Attr member of this Item with a Text key whose string value 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 Text key whose string value equals the given key. Equivalent to getAttr(Text), but avoids boxing the key string into a Text value.
  - getSlot
```
public abstract Value getSlot(Value key)
```
    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.
  - getSlot
```
public abstract Value getSlot(String key)
```
    Returns the value of the last Slot member of this Item with a Text key whose string value 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 Text key whose string value equals the given key. Equivalent to getSlot(Value), but avoids boxing the key string into a Text value.
  - getField
```
public abstract Field getField(Value key)
```
    Returns the last Field member of this Item whose key is equal to the given key; returns null 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.
  - getField
```
public abstract Field getField(String key)
```
    Returns the last Field member of this Item with a Text key whose string value is equal to the given key; returns null if this Item is not a Record, or if this Item is a Record, but has no Field member with a Text key whose string value equals the given key. Equivalent to getField(Value), but avoids boxing the key string into a Text value.
  - getItem
```
public abstract Item getItem(int index)
```
    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 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.
  - updated
```
public Record updated(Value key,
                      Value value)
```
  - updated
```
public Record updated(Value key,
                      String value)
```
  - updated
```
public Record updated(Value key,
                      int value)
```
  - updated
```
public Record updated(Value key,
                      long value)
```
  - updated
```
public Record updated(Value key,
                      float value)
```
  - updated
```
public Record updated(Value key,
                      double value)
```
  - updated
```
public Record updated(Value key,
                      boolean value)
```
  - updated
```
public Record updated(String key,
                      Value value)
```
  - updated
```
public Record updated(String key,
                      String value)
```
  - updated
```
public Record updated(String key,
                      int value)
```
  - updated
```
public Record updated(String key,
                      long value)
```
  - updated
```
public Record updated(String key,
                      float value)
```
  - updated
```
public Record updated(String key,
                      double value)
```
  - updated
```
public Record updated(String key,
                      boolean value)
```
  - updatedAttr
```
public Record updatedAttr(Text key,
                          Value value)
```
  - updatedAttr
```
public Record updatedAttr(Text key,
                          String value)
```
  - updatedAttr
```
public Record updatedAttr(Text key,
                          int value)
```
  - updatedAttr
```
public Record updatedAttr(Text key,
                          long value)
```
  - updatedAttr
```
public Record updatedAttr(Text key,
                          float value)
```
  - updatedAttr
```
public Record updatedAttr(Text key,
                          double value)
```
  - updatedAttr
```
public Record updatedAttr(Text key,
                          boolean value)
```
  - updatedAttr
```
public Record updatedAttr(String key,
                          Value value)
```
  - updatedAttr
```
public Record updatedAttr(String key,
                          String value)
```
  - updatedAttr
```
public Record updatedAttr(String key,
                          int value)
```
  - updatedAttr
```
public Record updatedAttr(String key,
                          long value)
```
  - updatedAttr
```
public Record updatedAttr(String key,
                          float value)
```
  - updatedAttr
```
public Record updatedAttr(String key,
                          double value)
```
  - updatedAttr
```
public Record updatedAttr(String key,
                          boolean value)
```
  - updatedSlot
```
public Record updatedSlot(Value key,
                          Value value)
```
  - updatedSlot
```
public Record updatedSlot(Value key,
                          String value)
```
  - updatedSlot
```
public Record updatedSlot(Value key,
                          int value)
```
  - updatedSlot
```
public Record updatedSlot(Value key,
                          long value)
```
  - updatedSlot
```
public Record updatedSlot(Value key,
                          float value)
```
  - updatedSlot
```
public Record updatedSlot(Value key,
                          double value)
```
  - updatedSlot
```
public Record updatedSlot(Value key,
                          boolean value)
```
  - updatedSlot
```
public Record updatedSlot(String key,
                          Value value)
```
  - updatedSlot
```
public Record updatedSlot(String key,
                          String value)
```
  - updatedSlot
```
public Record updatedSlot(String key,
                          int value)
```
  - updatedSlot
```
public Record updatedSlot(String key,
                          long value)
```
  - updatedSlot
```
public Record updatedSlot(String key,
                          float value)
```
  - updatedSlot
```
public Record updatedSlot(String key,
                          double value)
```
  - updatedSlot
```
public Record updatedSlot(String key,
                          boolean value)
```
  - appended
```
public Record appended(Item item)
```
  - appended
```
public Record appended(String item)
```
  - appended
```
public Record appended(int item)
```
  - appended
```
public Record appended(long item)
```
  - appended
```
public Record appended(float item)
```
  - appended
```
public Record appended(double item)
```
  - appended
```
public Record appended(boolean item)
```
  - appended
```
public Record appended(Object... items)
```
  - prepended
```
public Record prepended(Item item)
```
  - prepended
```
public Record prepended(String item)
```
  - prepended
```
public Record prepended(int item)
```
  - prepended
```
public Record prepended(long item)
```
  - prepended
```
public Record prepended(float item)
```
  - prepended
```
public Record prepended(double item)
```
  - prepended
```
public Record prepended(boolean item)
```
  - prepended
```
public Record prepended(Object... items)
```
  - removed
```
public abstract Item removed(Value key)
```
  - removed
```
public abstract Item removed(String key)
```
  - concat
```
public Record concat(Item that)
```
  - conditional
```
public abstract Item conditional(Item thenTerm,
                                 Item elseTerm)
```
  - or
```
public abstract Item or(Item that)
```
  - and
```
public abstract Item and(Item that)
```
  - bitwiseOr
```
public abstract Item bitwiseOr(Item that)
```
  - bitwiseXor
```
public abstract Item bitwiseXor(Item that)
```
  - bitwiseAnd
```
public abstract Item bitwiseAnd(Item that)
```
  - lt
```
public Item lt(Item that)
```
  - le
```
public Item le(Item that)
```
  - eq
```
public Item eq(Item that)
```
  - ne
```
public Item ne(Item that)
```
  - ge
```
public Item ge(Item that)
```
  - gt
```
public Item gt(Item that)
```
  - plus
```
public abstract Item plus(Item that)
```
  - minus
```
public abstract Item minus(Item that)
```
  - times
```
public abstract Item times(Item that)
```
  - divide
```
public abstract Item divide(Item that)
```
  - modulo
```
public abstract Item modulo(Item that)
```
  - not
```
public abstract Item not()
```
  - bitwiseNot
```
public abstract Item bitwiseNot()
```
  - negative
```
public abstract Item negative()
```
  - positive
```
public abstract Item positive()
```
  - inverse
```
public abstract Item inverse()
```
  - invoke
```
public Item invoke(Value args)
```
  - lambda
```
public abstract Value lambda(Value template)
```
  - filter
```
public Selector filter()
```
  - filter
```
public Selector filter(Item predicate)
```
  - max
```
public Item max(Item that)
```
  - min
```
public Item min(Item that)
```
  - evaluate
```
public Item evaluate(Interpreter interpreter)
```
  - evaluate
```
public Item evaluate(Item scope)
```
  - substitute
```
public Item substitute(Interpreter interpreter)
```
  - substitute
```
public Item substitute(Item scope)
```
  - stringValue
```
public abstract String stringValue()
```
    Converts this Item into a String value, if possible.
    
    Throws:
    
    UnsupportedOperationException - if this Item can't be converted into a String value.
  - stringValue
```
public abstract String stringValue(String orElse)
```
    Converts this Item into a String value, if possible; otherwise returns orElse if this Item can't be converted into a string value.
  - byteValue
```
public abstract byte byteValue()
```
    Converts this Item into a primitive byte value, if possible.
    
    Throws:
    
    UnsupportedOperationException - if this Item can't be converted into a primitive byte value.
  - byteValue
```
public abstract byte byteValue(byte orElse)
```
    Converts this Item into a primitive byte value, if possible; otherwise returns orElse if this Item can't be converted into a primitive byte value.
  - shortValue
```
public abstract short shortValue()
```
    Converts this Item into a primitive short value, if possible.
    
    Throws:
    
    UnsupportedOperationException - if this Item can't be converted into a primitive short value.
  - shortValue
```
public abstract short shortValue(short orElse)
```
    Converts this Item into a primitive short value, if possible; otherwise returns orElse if this Item can't be converted into a primitive short value.
  - intValue
```
public abstract int intValue()
```
    Converts this Item into a primitive int value, if possible.
    
    Throws:
    
    UnsupportedOperationException - if this Item can't be converted into a primitive int value.
  - intValue
```
public abstract int intValue(int orElse)
```
    Converts this Item into a primitive int value, if possible; otherwise returns orElse if this Item can't be converted into a primitive int value.
  - longValue
```
public abstract long longValue()
```
    Converts this Item into a primitive long value, if possible.
    
    Throws:
    
    UnsupportedOperationException - if this Item can't be converted into a primitive long value.
  - longValue
```
public abstract long longValue(long orElse)
```
    Converts this Item into a primitive long value, if possible; otherwise returns orElse if this Item can't be converted into a primitive long value.
  - floatValue
```
public abstract float floatValue()
```
    Converts this Item into a primitive float value, if possible.
    
    Throws:
    
    UnsupportedOperationException - if this Item can't be converted into a primitive float value.
  - floatValue
```
public abstract float floatValue(float orElse)
```
    Converts this Item into a primitive float value, if possible; otherwise returns orElse if this Item can't be converted into a primitive float value.
  - doubleValue
```
public abstract double doubleValue()
```
    Converts this Item into a primitive double value, if possible.
    
    Throws:
    
    UnsupportedOperationException - if this Item can't be converted into a primitive double value.
  - doubleValue
```
public abstract double doubleValue(double orElse)
```
    Converts this Item into a primitive double value, if possible; otherwise returns orElse if this Item can't be converted into a primitive double value.
  - integerValue
```
public abstract BigInteger integerValue()
```
    Converts this Item into a BigInteger value, if possible.
    
    Throws:
    
    UnsupportedOperationException - if this Item can't be converted into a BigInteger value.
  - integerValue
```
public abstract BigInteger integerValue(BigInteger orElse)
```
    Converts this Item into a BigInteger value, if possible; otherwise returns orElse if this Item can't be converted into a BigInteger value.
  - numberValue
```
public abstract Number numberValue()
```
    Converts this Item into a Number object, if possible.
    
    Throws:
    
    UnsupportedOperationException - if this Item can't be converted into a Number object.
  - numberValue
```
public abstract Number numberValue(Number orElse)
```
    Converts this Item into a Number object, if possible; otherwise returns orElse if this Item can't be converted into a Number object.
  - charValue
```
public abstract char charValue()
```
    Converts this Item into a primitive char value, if possible.
    
    Throws:
    
    UnsupportedOperationException - if this Item can't be converted into a primitive char value.
  - charValue
```
public abstract char charValue(char orElse)
```
    Converts this Item into a primitive char value, if possible; otherwise returns orElse if this Item can't be converted into a primitive char value.
  - booleanValue
```
public abstract boolean booleanValue()
```
    Converts this Item into a primitive boolean value, if possible.
    
    Throws:
    
    UnsupportedOperationException - if this Item can't be converted into a primitive boolean value.
  - booleanValue
```
public abstract boolean booleanValue(boolean orElse)
```
    Converts this Item into a primitive boolean value, if possible; otherwise returns orElse if this Item can't be converted into a primitive boolean value.
  - cast
```
public <T> T cast(Form<T> form)
```
  - cast
```
public <T> T cast(Form<T> form,
                  T orElse)
```
  - coerce
```
public <T> T coerce(Form<T> form)
```
  - coerce
```
public <T> T coerce(Form<T> form,
                    T orElse)
```
  - isAliased
```
public abstract boolean isAliased()
```
  - isMutable
```
public abstract boolean isMutable()
```
  - alias
```
public abstract void alias()
```
  - branch
```
public abstract Item branch()
```
  - commit
```
public abstract Item commit()
```
    Flags this Item as immutable, recursively if it is a Record, then returns this Item.
  - precedence
```
public int precedence()
```
  - iterator
```
public Iterator<Item> iterator()
```
    Specified by:
    
    iterator in interface Iterable<Item>
  - typeOrder
```
public abstract int typeOrder()
```
    Returns the heterogeneous sort order of this Item. Used to impose a total order on the set of all items. When comparing two items of different types, the items order according to their typeOrder.
  - compareTo
```
public abstract int compareTo(Item other)
```
    Specified by:
    
    compareTo in interface Comparable<Item>
  - keyEquals
```
public abstract boolean keyEquals(Object key)
```
  - equals
```
public abstract boolean equals(Object other)
```
    Overrides:
    
    equals in class Object
  - hashCode
```
public abstract int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - debug
```
public abstract <T> Output<T> debug(Output<T> output)
```
    Description copied from interface: Debug
    
    Writes a developer readable, debug-formatted string representation of this object to output.
    
    Specified by:
    
    debug in interface Debug
    
    Returns:
    
    the continuation of the output.
  - display
```
public <T> Output<T> display(Output<T> output)
```
    Description copied from interface: Display
    
    Writes a human readable, display-formatted string representation of this object to output.
    
    Specified by:
    
    display in interface Display
    
    Returns:
    
    the continuation of the output.
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - empty
```
public static Item empty()
```
  - extant
```
public static Item extant()
```
  - absent
```
public static Item absent()
```
  - fromObject
```
public static Item fromObject(Object object)
```
  - globalScope
```
public static Item globalScope()
```

Class Item

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface java.lang.Iterable

Method Detail

isDefined

isDistinct

isDefinite

isConstant

key

toValue

tag

target

flattened

unflattened

header

headers

head

tail

body

length

contains

containsKey

containsKey

containsValue

get

get

getAttr

getAttr

getSlot

getSlot

getField

getField

getItem

updated

updated

updated

updated

updated

updated

updated

updated

updated

updated

updated

updated

updated

updated

updatedAttr

updatedAttr

updatedAttr

updatedAttr

updatedAttr

updatedAttr

updatedAttr

updatedAttr

updatedAttr

updatedAttr

updatedAttr

updatedAttr

updatedAttr

updatedAttr

updatedSlot

updatedSlot

updatedSlot

updatedSlot

updatedSlot

updatedSlot

updatedSlot

updatedSlot

updatedSlot

updatedSlot

updatedSlot

updatedSlot

updatedSlot

updatedSlot

appended

appended

appended

appended