mentoring notes for Bob on the Ruby track

tracks/ruby/exercises/bob/mentoring.md

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+# Mentoring
+
+The key to this exercise is to look for patterns in a string, and extracting the specific criteria in order to make return the correct response.
+Most solutions look for `yelling` and `asking` criteria.
+
+## Resonable Solutions
+
+### Using String Methods
+
+```ruby
+module Bob
+
+  def self.hey(remark)
+    remark = remark.strip
+    question = remark.end_with?('?')
+    yelling = remark == remark.upcase && remark != remark.downcase
+
+    if remark.empty?
+      'Fine. Be that way!'
+    elsif yelling && question
+      "Calm down, I know what I'm doing!"
+    elsif yelling
+      'Whoa, chill out!'
+    elsif question
+      'Sure.'
+    else
+      'Whatever.'
+    end
+  end
+
+end
+```
+
+### Using Regular Expressions
+
+```ruby
+module Bob
+
+  SILENCE = /\A\s*\z/
+  ASKING = /\?\s*\z/
+  SHOUTING = /\A[^A-Za-z]*[A-Z]+(?:[^a-z]*)\z/
+  def self.hey(input)
+    case
+    when silence?(input)
+      'Fine. Be that way!'
+    when asking?(input) && shouting?(input)
+      "Calm down, I know what I'm doing!"
+    when asking?(input)
+      'Sure.'
+    when shouting?(input)
+      'Whoa, chill out!'
+    else
+      'Whatever.'
+    end
+  end
+
+  class << self
+    protected
+    def silence?(input)
+      SILENCE.match?(input)
+    end
+
+    def shouting?(input)
+      SHOUTING.match?(input)
+    end
+
+    def asking?(input)
+      ASKING.match?(input)
+    end
+  end
+end
+```
+
+## Common Suggestions
+
+### Predicate Methods
+
+The names of predicate methods (methods that return a boolean value) should end in a question mark (i.e. `Array#empty?`).
+
+Students should avoid prefixing predicate methods with auxiliary verbs such as `is_yelling` or `has_question`
+These words are redundant and inconsistent with the style of boolean methods in the Ruby core library, such as `empty?` and `include?`.
+
+Resources about style:
+- https://rubystyle.guide/#bool-methods-qmark
+- https://rubystyle.guide/#bool-methods-prefix
+
+### Checking for a Question Mark With Indices
+
+If the student is using indices or extra transforms to check for a question mark (e.g., `remark[-1] == '?'`, `remark.chars.last == '?'`, etc.), guide them toward `String#end_with?`.
+It is more readable and explicitly communicates the intent of the check.
+
+### Usage of Regular Expressions
+
+Regular expressions are powerful, but can be illegible.
+While regex is common in Ruby code, if the student is having a hard time understanding regex it may be better to guide them toward a solution that uses simpler String methods.