Dynamic code loading - Lua example

Functions. example from a Well House Consultants training course
More on Functions. [link]

This example is described in the following article(s):
• Lua examples - coroutines, error handling, objects, etc - [link]

Source code: fcv Module: U106

--[[

Because functions are "first class variables" in Lua and share the
same name space, you can dynamically load and assign them. In this
example, we've re-used a variable called john that contained a number
to contain a function, given it another name called jane are then
assigned a string to john !!!

It's very much a demonstration in this case - I would NOT normally
replace a piece of code with an integer or string (or vice versa) but
the reassignment of a function IS useful. It means that standard code
can be provided by a vendor who embeds lua, but then the knowledgable
user can override it. A very powerful facility ...

]]

io.write ("How old? ")
john = tonumber(io.read())

print (john)

if john > 30 then
function john()
        return 42
        end
else
function john()
        return 22
        end
end

jane = john

john = "A person"

print (jane())

Learn about this subject

This module and example are covered on the following public courses:
* Learning to program in Lua
* Lua Programming
* Lua Programming
Also available on on site courses for larger groups

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