[ruby-core:99443] [Ruby master Bug#17098] Float#negative? reports negative zero as not negative
From:
marcandre-ruby-core@...
Date:
2020-08-01 19:41:08 UTC
List:
ruby-core #99443
Issue #17098 has been updated by marcandre (Marc-Andre Lafortune). AFAIK, the only way to check for `-0.0` is `1.0 / var == -Float::INFINITY` I find it difficult to discuss what need to be done about any of this as I do not know of the use cases for `-0.0`; without them it seems very theoretical. ---------------------------------------- Bug #17098: Float#negative? reports negative zero as not negative https://bugs.ruby-lang.org/issues/17098#change-86898 * Author: chrisseaton (Chris Seaton) * Status: Open * Priority: Normal * Backport: 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN ---------------------------------------- Is this intended behaviour? ``` irb(main):001:0> neg_zero = -0.0 => -0.0 irb(main):002:0> neg_zero.negative? => false irb(main):003:0> neg_zero < 0 => false ``` It happens because `Numeric#negative?` uses `< 0`. My understanding of IEEE floating point is that negative zero is not less than zero, but I think it should still report as negative. -- https://bugs.ruby-lang.org/ Unsubscribe: <mailto:[email protected]?subject=unsubscribe> <http://lists.ruby-lang.org/cgi-bin/mailman/options/ruby-core>