questions.txt

Please Read: 
 - Chapter 6 Standard Types
 - Review Blocks
 - Chapter 7 Regular Expressions
 - Chapter 22 The Ruby Language: basic types (symbols), variables and constants

1. What is a symbol?

A: A symbol is Ruby's immutable string-like unique primative, used when creating a variable that stands for something significant, much like enumerables in other languages. An example might be creating a symbol for each direction like :up, :down, :left. :right.

2. What is the difference between a symbol and a string?

A: Strings are mutable, symbols are immutable. 

3. What is a block and how do I call a block?

A: Blocks are chunks of code inbetween delimeters, curly braces or keywords 'do' and 'end'. Blocks are called with a method name, code wrapped in the do and end keywords and any parameters passed to the block with pipes '|' on either side.

method_name {|parameter| parameter.work}

4. How do I pass a block to a method? What is the method signature?

A: You can pass a block to a method by immediately including a block following a method name. The method signature does not have to be special, and does not have to take any special parameters. However to emit values to a block, the method definition needs to contain the yield keyword. 

method_name {|parameter| parameter.work}

5. Where would you use regular expressions?

A: Regular expressions are used in any situation that calls for string finding/matching. Regex's can be used for user input validation, manipulation/searching of large text files, or even extraction of values from unstructured data.