[Understanding] Differences between hashes and arrays in Ruby


I was learning ruby and could only understand the hashes and arrays that I often see, but I've finally come to understand it recently, so I summarized it! You can see the difference between hashes and arrays by looking at this! (Perhaps)

First of all, the array

What is an array?

name = ["Suzuki","Tanaka","Onishi"]

--Multiple elements are lined up --Enclosed in [] --Elements are separated by , --Subscripts are specified as integers in order from the front (in the above, name (1) =>" Tanaka ")

What is a hash?

Hash is like this

name = { a: "Suzuki",b: "Tanaka",c: "Onishi" }

--Hash is essentially the same as an array --Enclosed in {} -** You can specify a key (subscript) other than an integer! ** It may be exhausted (in the above, name [: a] =>" Suzuki ")

Why use {} when they are essentially the same

If the hash is surrounded by [], it's easy to lose track of what is the attribute and what is the key, so it's the hash that's surrounded by {}! It seems that it is used to make it easier to understand!

If you know this, it will be easier to distinguish when studying or reading the code!

that's all~

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