Sha256: 6fe0c7387bbb2bca7c0323e2f57db3f9982c113da68a3e063618e14d3198fc76
Contents?: true
Size: 593 Bytes
Versions: 11
Compression:
Stored size: 593 Bytes
Contents
# Adapted from http://stackoverflow.com/questions/2709361/monad-equivalent-in-ruby
class LazyIdentity # :nodoc:
def initialize(lam = nil, &blk)
@lazy = lam || blk
@lazy.is_a?(Proc) || raise(ArgumentError, "not a Proc")
@lazy.arity.zero? || raise(ArgumentError, "arity must be 0, was #{@lazy.arity}")
end
attr_reader :lazy
def force
@lazy[]
end
def self.unit(lam = nil, &blk)
LazyIdentity.new(lam || blk)
end
def bind(lam = nil, &blk)
f = lam || blk
f[@lazy]
end
def ==(other)
other.is_a?(LazyIdentity) && other.force == force
end
end
Version data entries
11 entries across 11 versions & 1 rubygems