Find occurrences of bools

visitor.cr

class BooleanVisitor < Crystal::Visitor
  def visit(node : Crystal::BoolLiteral)
    puts "Line: #{node.location.try &.line_number}"
    puts "Column: #{node.location.try &.column_number}"
    true
  end

  def visit(node : Crystal::ASTNode)
    true
  end
end

ast.accept(BooleanVisitor.new)

# => will print:
# Line: 2
# Column: 3