Learn Red - Fundamentals of Red

Questions

1. Run the following code,  both interpreted and compiled.

      mycode: [prnt "Hello" halt]      do mycode

Explain the results. 

2. Rewrite the first do example in this chapter with does.
3. What is the difference between the has1 and has2 functions in the following code?

      has1: has [][          num: 108 - 42          print num      ]      has2: has [num][          num: 108 - 42          print num      ]

4. What are the values of num1 and num2 after executing the following code? Explain.

      ex-glob: function [          /extern num1 ]       [          num1: 13           num2: 42      ]      num1: 100 ;== 100      num2: 200 ;== 200      ex-glob

5. Define a sum function that sums two numbers, n and m. Use argument typing.
6. Write a testref function that takes two number parameters. The function should have a /add  refinement that returns their sum, and ...