Sha256: 55d3bfe721b9804b597422e6e62aa6f827f0e474cdc8abb4b8a4801e1839ff32
Contents?: true
Size: 1.23 KB
Versions: 5
Compression:
Stored size: 1.23 KB
Contents
class Range
def bsearch
return to_enum(__method__) unless block_given?
from = self.begin
to = self.end
unless from.is_a?(Numeric) && to.is_a?(Numeric)
raise TypeError, "can't do binary search for #{from.class}"
end
midpoint = nil
if from.is_a?(Integer) && to.is_a?(Integer)
convert = Proc.new{ midpoint }
else
map = Proc.new do |pk, unpk, nb|
result, = [nb.abs].pack(pk).unpack(unpk)
nb < 0 ? -result : result
end.curry
i2f = map['q', 'D']
f2i = map['D', 'q']
from = f2i[from.to_f]
to = f2i[to.to_f]
convert = Proc.new{ i2f[midpoint] }
end
to -= 1 if exclude_end?
satisfied = nil
while from <= to do
midpoint = (from + to).div(2)
result = yield(cur = convert.call)
case result
when Numeric
return cur if result == 0
result = result < 0
when true
satisfied = cur
when nil, false
# nothing to do
else
raise TypeError, "wrong argument type #{result.class} (must be numeric, true, false or nil)"
end
if result
to = midpoint - 1
else
from = midpoint + 1
end
end
satisfied
end unless method_defined? :bsearch
end
Version data entries
5 entries across 5 versions & 1 rubygems