property/equatable.fz
# This file is part of the Fuzion language implementation.
#
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# -----------------------------------------------------------------------
#
# Tokiwa Software GmbH, Germany
#
# Source code of Fuzion standard library feature equatable
#
# Author: Fridtjof Siebert (siebert@tokiwa.software)
#
# -----------------------------------------------------------------------
# equatable -- feature for immutable values that define an equality relation
#
public equatable is
# equality implements the default equality relation for values of this type.
#
# This relation must be
#
# - reflexive (equality a b),
# - symmetric (equality a b = equality b a), and
# - transitive ((equality a b && equality b c) : equality a c).
#
# result is true iff 'a' is considered to represent the same abstract value
# as 'b'.
#
public type.equality(a, b equatable.this) bool => abstract
last changed: 2024-03-07