Class IdentityMap
extends Map
A map that uses object identity instead of the == operator to test equality of keys. This map still uses the hash-code method on keys (see Map). There is no identity hash code operation on arbitrary classes in Toit.
Class summary
| operator == other/any -> bool | Whether this object is equal to the other. |
|---|---|
| clear -> none | Removes all elements from this instance. |
| size -> int | The number of elements in this instance. |
| is-empty -> bool | Whether this instance is empty. |
| contains key/any -> bool | Whether this instance contains the given key. |
| contains-all collection/Collection -> bool | Whether this instance contains all elements of collection. |
| remove key/any -> none | Removes the given key from this instance. |
| remove key/any [--if-absent] -> none | Removes the given key from this instance. |
| remove-all collection/Collection -> none | Removes all elements of collection from this instance. |
| operator [] key/any -> any | Returns the element stored at location key. |
| operator []= key/any value/any -> any | Stores value in the location for the given key. |
| get key/any -> any | Retrieves the value for key. |
| get key/any [--if-absent] -> any | Retrieves the value for key. |
| get key/any [--if-present] -> any | Retrieves the value for key. |
| get key/any [--if-present] [--if-absent] -> any | Retrieves the value for key. |
| get key/any [--init] -> any | Retrieves the value for key. |
| update key/any [updater] -> any | Updates the value of the given key. |
| update key/any [updater] [--if-absent] -> any | Updates the value of the given key. |
| update key/any [updater] --if-absent/any -> any | Updates the value of the given key. |
| update key/any [--init] [updater] -> any | Updates the value of the given key. |
| update key/any --init/any [updater] -> any | Updates the value of the given key. |
| do [block] -> none | Invokes the given block on each key/value pair of this instance. |
| do --reversed/True [block] -> none | |
| do --keys/True --reversed/bool= [block] -> none | Invokes the given block on each key of this instance. |
| do --values/True --reversed/bool= [block] -> none | Invokes the given block on each value of this instance. |
| keys -> List | Returns the keys of this instance as a list. |
| values -> List | Returns the values of this instance as a list. |
| reduce --values/True [block] -> any | Reduces the values of the map into a single value. |
| reduce --values/True --initial/any [block] -> any | Reduces the values of the map into a single value. |
| reduce --keys/True [block] -> any | Reduces the keys of the map into a single value. |
| reduce --keys/True --initial/any [block] -> any | Reduces the keys of the map into a single value. |
| reduce --initial/any [block] -> any | Reduces the map entries into a single value. |
| any --keys/True [predicate] -> bool | Whether at least one key in the map satisfies the given predicate. |
| any --values/True [predicate] -> bool | Whether at least one value in the map satisfies the given predicate. |
| any [predicate] -> bool | Whether at least one key-value pair in the map satisfies the given predicate. |
| every --keys/True [predicate] -> bool | Whether all keys in the map satisfy the given predicate. |
| every --values/True [predicate] -> bool | Whether all values in the map satisfy the given predicate. |
| every [predicate] -> bool | Whether all key-value pairs in the map satisfy the given predicate. |
| copy -> Map | Copies the map. |
| map [block] -> Map | Invokes the given block on each key/value pair and returns a new map with the results. |
| map --in-place/True [block] -> none | Maps the values of this instance. |
| filter --in-place/bool= [predicate] -> Map | Filters this instance using the given predicate. |
| stringify -> string | |
| first -> any | The first key of the map by insertion order. |
| last -> any | The last key of the map by insertion order. |
Methods
Whether at least one key in the map satisfies the given predicate.
Returns false, if the map is empty.
Whether at least one value in the map satisfies the given predicate.
Returns false, if the map is empty.
Whether at least one key-value pair in the map satisfies the given predicate.
The predicate block is called with two arguments: a key, and its value.
Returns false, if the map is empty.
Removes all elements from this instance.
Whether this instance contains all elements of collection.
Invokes the given block on each key/value pair of this instance.
The key/value pairs are iterated in key insertion order.
Users must not modify this instance while iterating over it.
Iterates over all key/value pairs in reverse order.
Users must not modify this instance while iterating over it.
Invokes the given block on each key of this instance.
Users must not modify this instance while iterating over it.
Invokes the given block on each value of this instance.
Users must not modify this instance while iterating over it.
Whether all keys in the map satisfy the given predicate.
Returns true, if the map is empty.
Whether all values in the map satisfy the given predicate.
Returns true, if the map is empty.
Whether all key-value pairs in the map satisfy the given predicate.
The predicate block is called with two arguments: a key, and its value.
Returns true, if the map is empty.
Filters this instance using the given predicate.
Returns this instance if in-place is true. In this case removes the elements that don't match the predicate.
Returns a new map if in-place is false (the default).
The result contains all the elements of this instance for which the predicate returns true.
Users must not otherwise modify this instance during the operation.
The first key of the map by insertion order.
Throws an error if the map is empty.
Retrieves the value for key.
Returns the value verbatim, if the key is contained in the map.
Returns null, otherwise.
Retrieves the value for key.
Returns the value verbatim, if this instance contains the key.
Otherwise, calls if-absent with the key and returns the result of the call.
Retrieves the value for key.
If this instance contains the key calls if-present with the corresponding value and returns the result.
Returns null otherwise.
Retrieves the value for key.
If this instance contains the key calls if-present with the corresponding value and returns the result.
Otherwise, calls if-absent with the key and returns the result of the call.
Retrieves the value for key.
Returns the value verbatim, if this instance contains the key.
Otherwise, initializes the slot with the result of calling init first.
Returns the keys of this instance as a list.
This operation instantiates a fresh list and is thus in O(n).
The last key of the map by insertion order.
Throws an error if the map is empty.
Invokes the given block on each key/value pair and returns a new map with the results.
The block is invoked with two arguments for each entry in this instance: the key and the value. The returned value becomes the new value for the key.
Examples
map := { "a": 1, "b": 2 }
// Double the values. (Key is not used).
doubled := map.map: | _ value | value * 2
print doubled // => { "a": 2, "b": 4 }
// Prefix the values with the key.
prefixed := map.map: | key value | "$key-$value"
print prefixed // => { "a": "a-1", "b": "b-2" }
Maps the values of this instance.
Invokes the given block on each key/value pair and replaces the old value with the result of the call.
Returns the element stored at location key.
The key must be in the map.
Stores value in the location for the given key.
If the key is already present, overrides the previous value.
Whether this object is equal to the other.
Inheritance
Classes overwrite this operator to get an equality specific to their needs. Equality operators often compare the type and field contents. For example:
class Pin:
number/int
constructor .number:
operator == other:
if other is not Pin: return false
return number == other.number
A class doesn't have to follow the above format, but it must keep the operator in sync with any
hash-code method. That is, if a class has a hash-code member, then the equality and hash-code must agree. If two instances are equal (a == b), then their hash codes must also be equal (a.hash-code == b.hash-code).Reduces the values of the map into a single value.
Reduces the values of the map into a single value.
Reduces the keys of the map into a single value.
Reduces the keys of the map into a single value.
Reduces the map entries into a single value.
The given block is called with three arguments: 1. the accumulated result, so far 2. the key of the current entry 3. the value of the current entry.
Removes the given key from this instance.
The key does not need to be present.
Removes the given key from this instance.
If the key is absent, calls if-absent with the key.
Removes all elements of collection from this instance.
Updates the value of the given key.
Calls the updater with the current value, and replaces the old value with the result.
Returns the result of calling the updater.
This instance must contain the key.
Updates the value of the given key.
If this instance contains the key, calls the updater with the current value, and replaces the old value with the result. Returns the result of the call.
If this instance does not contain the key, calls if-absent with the key instead, and stores the result of the call in this instance. Returns the result of the call.
Updates the value of the given key.
If this instance contains the key, calls the updater with the current value, and replaces the old value with the result. Returns the result of the call.
If this instance does not contain the key, stores if-absent in this instance. Returns if-absent.
Updates the value of the given key.
If this instance does not contain the key, calls init with the key first, and stores it in this instance.
Calls the updater with the current value (which might be the initial value that was just stored) and replaces the old value with the result.
Returns the result of the call to the updater.
Updates the value of the given key.
If this instance does not contain the key, stores init in this instance.
Calls the updater with the current value (which might be the initial value that was just stored) and replaces the old value with the result.
Returns the result of the call to the updater.
Returns the values of this instance as a list.
This operation instantiates a fresh list and is thus in O(n).