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Ruby Ruby Objects and Classes Build a Bank Account Class Part 3: Keeping Our Balance

vo thi quynh yen
vo thi quynh yen
3,129 Points
Posted by vo thi quynh yen
vo thi quynh yen
3,129 Points

@transactions.each do |transaction| balance += transaction[:amount] end

Why do I need to use the [] behind transaction? can't I use {}?

3 Answers

Michael Hulet
Michael Hulet
47,912 Points
Michael Hulet
Michael Hulet
47,912 Points

You use square brackets ([]) to get values out of both arrays and hashes. This is called "subscripting". There's no difference in the way you access values between arrays and hashes. In fact, you can generally think of an array as a hash with only sequential FixNum keys

Cindy Lea
PLUS
Cindy Lea
Courses Plus Student 6,497 Points
Cindy Lea
Cindy Lea
Courses Plus Student 6,497 Points

[] are usually used for array elements & the {} is used to group code so theyre 2 different things.

vo thi quynh yen
vo thi quynh yen
3,129 Points
vo thi quynh yen
vo thi quynh yen
3,129 Points

but i thought because transactions is a hash, and a hash syntax is {}, so why do I have to use [] instead of {} when refering to an element in a hash?