Ruby example - define and call a named block of code

Programming Principles example from a Well House Consultants training course
More on Programming Principles [link]

This example is described in the following article(s):
• New to programming? It is natural (but needless) for you to be nervous - [link]

Source code: rubfunc1 Module: Q101

# Define a named block of code which can be performed on
# a whole lot of type of data - for example, reading in
# an integer, where you're checking it is within a range,
# and you have a different question each time you call it

def getval(question,lowest,highest)
        result = 0
        loop do
                print question," - "
                result = STDIN.gets.to_i
                break if result >= lowest and result <= highest
                print "Not in range ",lowest," to ",highest,"\n"
        end
        return result
end

# Note - by this point in the code, you have ONLY defined the
# 'function' called getval - you haven't actually called (run)
# it yet!

# I can not call that code as and when I need to ....
# ... saving repetition of all the stuff inside the function
# (later - we'll move the function definition to another file
# and share it between lots of programs!)

r1 = getval("How long is this course?",1,5)
r2 = getval("What hour is it",0,23)
r3 = getval("What room shall we book next",1,5)

# print - all on one line, nothing between items
print "length: ",r1," start hour: ",r2," room: ",r3,"\n"

# puts - each on a line on its own
# (adds a new line AFTER each element!)
puts r1,r2,r3

Learn about this subject

This module and example are covered on the following public courses:
* Learning to program in PHP
* Learning to program in Python
* Learning to Program in Java
* Learning to program in Lua
* Learning to program in Ruby
* Learning to program in Tcl
* Learning to Program in C
* Learning to program in C and C++
* Learning to program in Perl
* Learning to program in PHP
* Learning to program in C and C++
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