Bug #7728

Range#bsearch on other Numerics?

Added by Marc-Andre Lafortune over 1 year ago. Updated about 1 year ago.

[ruby-core:51573]
Status:Closed
Priority:Normal
Assignee:Marc-Andre Lafortune
Category:core
Target version:2.0.0
ruby -v:r38825 Backport:

Description

Range#bsearch attempts to do something on generic Numeric classes.

I feel it is both useless and buggy:

(Rational(-1,2)..Rational(9,4)).bsearch{|x| true} # => yields with 7/8 and 33/16
(Rational(-1,2)..Rational(9,4)).bsearch{|x| false} # => loops forever
(BigDecimal('0.5')..BigDecimal('2.25'))... # => same

I feel the current implementation (aside from the bugs) only makes sense on Integers.

Possible approaches:

  • Rational
    1) convert to float, or
    2) bsearch accepts a "max iterations" parameter (which would be required for Rational), or
    3) forbid altogether

  • BigDecimal
    1) convert to float, or
    2) look at the space of decimal numbers in the range without a higher precision than begin or end.

Given the timeframe though, I recommend we raise a TypeError for both in 2.0.0 (or a NotImplemented if we decide what should be done).

Associated revisions

Revision 38985
Added by Marc-Andre Lafortune about 1 year ago

  • range.c: Restrict bsearch to integers [#7728]

  • test/ruby/test_range.rb: Test for above

History

#1 Updated by Marc-Andre Lafortune about 1 year ago

  • Status changed from Open to Closed
  • Assignee set to Marc-Andre Lafortune

Resolved with r38985.

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