Ruby

Question 1

What is the difference between map and collect?

Answer 1

There is none, collect is an alias for map in ruby. They both invoke a block once for each element in ‘self’. Eg:

xyz.collect { |x| x * 2 }

Question 2

Whats the ternary operator in rails?

Answer 2

Its a one line ifelse statement statement

@item.property = params[:property] ? true : false 

for example

var = 5;
var_is_greater_than_three = (var > 3 ? true : false);
puts var_is_greater_than_three

The values true and false can be replaced with strings, numbers, or other data types.

Question 3

What is ‘self’ in ruby?

Answer 3

Its a keyword that gives you access to the current object.