Comparator that efficienlty use to_s to compare things

The comparaison call to_s on object and use the result to order things.

var a = [1, 2, 3, 10, 20]
(new CachedAlphaComparator).sort(a)
assert a == [1, 10, 2, 20, 3]

Internally the result of to_s is cached in a HashMap to counter uneficient implementation of to_s.

Note: it caching is not usefull, see alpha_comparator

Introduced properties

Redefined properties

redef type COMPARED: Object

core $ CachedAlphaComparator :: COMPARED

What to compare to
redef type SELF: CachedAlphaComparator

core $ CachedAlphaComparator :: SELF

Type of this instance, automatically specialized in every class
redef fun compare(a: COMPARED, b: COMPARED): Int

core $ CachedAlphaComparator :: compare

Compare a and b.

All properties

fun !=(other: nullable Object): Bool

core :: Object :: !=

Have self and other different values?
fun ==(other: nullable Object): Bool

core :: Object :: ==

Have self and other the same value?
type CLASS: Class[SELF]

core :: Object :: CLASS

The type of the class of self.
type COMPARED: nullable Object

core :: Comparator :: COMPARED

What to compare to
type SELF: Object

core :: Object :: SELF

Type of this instance, automatically specialized in every class
fun bubble_sort(array: Array[COMPARED], from: Int, to: Int)

core :: Comparator :: bubble_sort

Bubble-sort array between from and to indices
protected fun class_factory(name: String): CLASS

core :: Object :: class_factory

Implementation used by get_class to create the specific class.
fun class_name: String

core :: Object :: class_name

The class name of the object.
abstract fun compare(a: COMPARED, b: COMPARED): Int

core :: Comparator :: compare

Compare a and b.
fun get_class: CLASS

core :: Object :: get_class

The meta-object representing the dynamic type of self.
fun hash: Int

core :: Object :: hash

The hash code of the object.
fun heap_sort(array: Array[COMPARED], from: Int, to: Int)

core :: Comparator :: heap_sort

Heap-sort array between from and to indices
init init

core :: Object :: init

fun insertion_sort(array: Array[COMPARED], from: Int, to: Int)

core :: Comparator :: insertion_sort

Insertion-sort array between from and to indices
fun inspect: String

core :: Object :: inspect

Developer readable representation of self.
protected fun inspect_head: String

core :: Object :: inspect_head

Return "CLASSNAME:#OBJECTID".
intern fun is_same_instance(other: nullable Object): Bool

core :: Object :: is_same_instance

Return true if self and other are the same instance (i.e. same identity).
fun is_same_serialized(other: nullable Object): Bool

core :: Object :: is_same_serialized

Is self the same as other in a serialization context?
intern fun is_same_type(other: Object): Bool

core :: Object :: is_same_type

Return true if self and other have the same dynamic type.
fun is_sorted(seq: SequenceRead[COMPARED]): Bool

core :: Comparator :: is_sorted

Is seq sorted?
fun max(a: COMPARED, b: COMPARED): COMPARED

core :: Comparator :: max

Returns the maximum between a and b.
fun merge_sort(array: Array[COMPARED], from: Int, to: Int)

core :: Comparator :: merge_sort

Merge-sort array between from and to indices
fun min(a: COMPARED, b: COMPARED): COMPARED

core :: Comparator :: min

Returns the minimum between a and b.
intern fun object_id: Int

core :: Object :: object_id

An internal hash code for the object based on its identity.
fun output

core :: Object :: output

Display self on stdout (debug only).
intern fun output_class_name

core :: Object :: output_class_name

Display class name on stdout (debug only).
fun quick_sort(array: Array[COMPARED], from: Int, to: Int)

core :: Comparator :: quick_sort

Quick-sort array between from and to indices
fun serialization_hash: Int

core :: Object :: serialization_hash

Hash value use for serialization
fun sort(array: Array[COMPARED])

core :: Comparator :: sort

Sort array using the compare function.
intern fun sys: Sys

core :: Object :: sys

Return the global sys object, the only instance of the Sys class.
abstract fun to_jvalue(env: JniEnv): JValue

core :: Object :: to_jvalue

fun to_s: String

core :: Object :: to_s

User readable representation of self.
package_diagram core::CachedAlphaComparator CachedAlphaComparator core::Comparator Comparator core::CachedAlphaComparator->core::Comparator core::Object Object core::Comparator->core::Object ...core::Object ... ...core::Object->core::Object

Ancestors

interface Object

core :: Object

The root of the class hierarchy.

Parents

interface Comparator

core :: Comparator

This abstract class generalizes ways to sort an array

Class definitions

core $ CachedAlphaComparator
# Comparator that efficienlty use `to_s` to compare things
#
# The comparaison call `to_s` on object and use the result to order things.
#
# ~~~
# var a = [1, 2, 3, 10, 20]
# (new CachedAlphaComparator).sort(a)
# assert a == [1, 10, 2, 20, 3]
# ~~~
#
# Internally the result of `to_s` is cached in a HashMap to counter
# uneficient implementation of `to_s`.
#
# Note: it caching is not usefull, see `alpha_comparator`
class CachedAlphaComparator
	super Comparator
	redef type COMPARED: Object

	private var cache = new HashMap[Object, String]

	private fun do_to_s(a: Object): String do
		if cache.has_key(a) then return cache[a]
		var res = a.to_s
		cache[a] = res
		return res
	end

	redef fun compare(a, b) do
		return do_to_s(a) <=> do_to_s(b)
	end
end
lib/core/text/abstract_text.nit:2464,1--2494,3