yield (co-routines / generator)
Control Structures example from a Well House Consultants training course
More on Control Structures [link]
Source code: yrb Module: R104
In Ruby, a named piece of code (method) can return a result
via a yield ... and then resume in due course. That
may sound a bit technical, but it allows you to code a function
which doesn't run through to completion at one go, but rather
returns results as it generates them, passing the results for
the calling code to handle as it will.
# This function includes yield, passing results back one at a time
i = current = previous = 1
# pass back what we have so far
yield 1 ; yield 1
while (i < limit)
temp = current
current += previous
previous = temp
# pass back what we have so far
i += 1
# And here is the call to the function - in this demonstration it's
# just a simple print loop but it could be much more!
fibonacci(15) do |dis|
Dorothy:rn grahamellis$ ruby yrb
Learn about this subject
This module and example are covered on the following public courses:
* Learning to program in Ruby
* Ruby Programming
Also available on on site courses for larger groups
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